Search results

A two‐dimensional model for hybrid circuits is presented in this paper. Simulation results of a hybrid power module for different power dissipation of components and ambient temperature are given. The experimental contribution is based on thermal measurements of the realized hybrid power module using a matrix of flip‐chip sensors. Thermal measurements were taken at different ambient temperatures and different hybrid module power values. The temperature distributions obtained theoretically and experimentally are compared and analyzed. Finally, the contribution of the temperature distributions and measured temperatures to the reliability of the hybrid power module is given.

The paper aims to focus on thick film planar thermistors.

Thick film planar thermistors such as rectangular, sandwich, multilayer, segmented and interdigitated were printed of law temperature NTC paste called NTC 3K3 95/2 (Ei Iritel). Their resistivity was measured at room temperature as a function of volume resistivity variations due to electrode effect (diffusion of PdAg into NTC layer) and variation of geometrical parameters such as length l, width w, thickness d, number of segments n. The experimental data obtained were used in forming a model by the simple fitting procedure for counting diffusion effect on volume resistivity and resistivity dependence on geometrical parameters.

Thermal behavior of NTC thick films was measured in the range of −30‐120°C. Exponential factor B was fitted for measured values and included in the proposed thick film thermistors model. The agreement of measured and calculated data enables simulation of new thermistor geometries.

The paper focuses on the experiment which was the first step in forming a total physical/mathematical model proposed for thick film thermistor resistivity.

The purpose of this paper is to apply negative thermal coefficient (NTC) thick film segmented thermistors (TFSTs) in a micro‐flow sensor for water.

A TFST is printed using NTC paste based on nickel manganite. The resistance of this thermistor is measured in a climatic chamber and the resulting curves are calibrated. A micro‐flow sensor is designed using a self‐heated segmented thermistor. The sensing principle is based on heat loss depending on the water flow intensity through the capillary. Water flow calibration is performed. The sensor sensitivity, inertia, and stability are analyzed.

The micro‐flow sensor exhibits good stability, suitable sensitivity, and inertia for integral measurements of water flow.

Advantages of a micro‐flow sensor using a TFST include low energy consumption, simple measuring procedure, and passive electronics.

This paper describes initial work on a micro‐flow sensor for water using TFSTs.

The purpose of this present study is to find a scientific method for the evaluation of environmental impacts according to the requirement 4.3.1.

To realize the objectives, the authors worked with a representative sample from certified ISO 14001 organizations. The data aim to identify and evaluate (according to the organization's methodology) significant environmental impacts. In this study, the authors created two models for the evaluation of environmental impacts based on an artificial neural network applied in the pilot organization and compared the results obtained from these models with those obtained by applying an analytic hierarchy process (AHP) method. AHP is part of an multi‐criteria decision making method and provides good multi‐criteria support for decision making for problems that can be structured hierarchically.

This paper presents a new approach that uses a backpropagation neural network to evaluate environmental impacts regardless of the organization type.

This paper presents a unique approach for the reliable and objective evaluation of environmental impacts.