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The embedding of passive components such as resistors, capacitors and inductors within printed circuit boards (PCBs) is motivated, to a large extent, by the desire for increased miniaturisation of electronic goods. However, resistors and, to a lesser extent, inductors are heat generating devices, and the temperature developed within PCBs as the result of the operation of embedded passives is a significant aspect of the design of a multilayer PCB. Here we investigate, by simulation, temperature fields associated with operation of embedded resistors. It is shown that for board dimensions less than 2cm × 2cm temperatures achieved are higher than those associated with larger boards having identical structures and identical resistor heat generation. Detailed simulations are used to investigate the sensitivity of the temperature rises associated with embedded resistors to copper track coverage and to thermal coupling of the PCB to ambient on its upper and lower surfaces. The implications of these findings are discussed both in the context of the design of real PCBs and in the context of thermal simulation.

In this paper, thermal analysis for a 1,200 A, 3.3 kV insulated gate bipolar transistor (IGBT) module was investigated and analysed using the three‐dimensional transmission line matrix (3D‐TLM) method. This paper also reviews the present status of the use of various thermal heat spreaders such as AlSiC MMC, Cu‐Mo and graphite‐Cu MMC and compares these with copper based heat spreaders and the use of aluminium nitride (AlN), diamond and BeO as substrates and their effect to dissipate the heat flux in heat sources localised in IGBT module design. The TLM method was found to be a versatile tool which is ideally suited to the modelling of many power electronic devices and which proved very useful in the study of transient thermal effects in a variety of device structures.

Numerical modelling is used to predict the thermal behaviour of embedded passive components in multi‐layer PCBs. A three‐signal layer PCB, containing embedded resistors of dimensions 0.3 6 0.3mm and thickness 0.1μm, is used to generate thermal design rules that can be applied to a wide range of PCB structures containing embedded passive components. A software package using the design rules can then make fast predictions on the thermal behaviour of heat‐generating components inside such structures.

Previous models of temperature development during the reflow soldering process have typically used commercially available, general purpose, finite difference/finite element modelling tools to create detailed three dimensional representations of both the product and of the reflow furnace. Such models have been shown to achieve a high degree of accuracy in predicting the temperatures a particular PCB design will achieve during the reflow process, but are complex to generate and analysis times are long, even when using modern high performance computer workstations.This paper will report on the development of a simplified model of the process, which uses less complex representations of both the product and the process, together with a simple numerical solver developed specifically for this application, whilst achieving an accuracy comparable with more detailed models. In the simplified model, the product is divided into elements, which are represented using a two‐dimensional mesh of thermal conductances linking thermal masses. The values of these conductances and masses are calculated based on the averaged properties of the PCB material and attached components within the area of each of the elements. The representation of the specific reflow furnace is based on measurements of the temperature and level of thermal convection at each point along the length of the furnace, thereby avoiding the necessity of making detailed measurements of the furnace geometry and air flow velocities. The combination of these two simplification techniques allow the reduction of analysis time for a relatively simple PCB from in the order of an hour on a high performance Unix workstation to under a second on a Pentium class PC running Microsoft Windows.

This paper aims to examine transferable skills and viable career transition pathways for hospitality and tourism workers. Future career prospects are discussed, along with the importance of reskilling for low-wage hospitality workers.

A network analysis is conducted to model skill relationships between the hospitality industry and other industries such as health-care and information technology. Multiple data are used in the analysis, including data from the US Department of Labor Occupational Information Network (O*NET), wage data from the Bureau of Labor Statistics and job computerization data (Frey and Osborne, 2017).

Although hospitality workers have lower than average skills scores when compared to workers from other career clusters included in the analysis, they possess essential soft skills that are valuable in other industries. Therefore, improving hospitality workers’ existing soft skills may help them enhance their cross-sector mobility, which may allow them to obtain jobs with a lower likelihood of computerization.

The findings shed light on workforce development theories and practice in the hospitality industry by quantitatively analyzing cross-sector skill correlations. Sharpening transferable soft skills will be essential to enhancing hospitality workers’ career development opportunities.

To the best of the authors’ knowledge, this is the first study that specifically examines the skill taxonomy for the hospitality industry and identifies its connection with other in-demand career clusters.

Gives a bibliographical review of the finite element meshing and remeshing from the theoretical as well as practical points of view. Topics such as adaptive techniques for meshing and remeshing, parallel processing in the finite element modelling, etc. are also included. The bibliography at the end of this paper contains 1,727 references to papers, conference proceedings and theses/dissertations dealing with presented subjects that were published between 1990 and 2001.

Power modules including the insulated gate bipolar transistor (IGBT) are widely used in the applications of motor drivers. The thermal behavior of these modules makes it important to choose the optimum design of cooling system. The purpose of this paper is to propose an RC thermal model of the dynamic electro‐thermal behavior of IGBT pulse width modulation inverter modules.

The electrothermal model has been implemented and simulated with a MATLAB simulator and takes into account the thermal influence between the different module chips based on the technique of superposition.

This study has led to a correction of the junction temperature values estimated from the transient thermal impedance of each component operating alone.

In this paper, an experimental technique of a thermal influence evaluation is presented.

This study aims to investigate the behavior of different types of stone columns, including the short and floating columns, as well as the ordinary and the geosynthetic encased stone columns (OSC and GESC). The effectiveness of the geosynthetic encasement and the impact of the installation using the lateral expansion method on the column performance is evaluated through a three-dimensional (3D) unit cell numerical analysis.

A full 3D numerical analysis is carried out using the explicit finite element code PLAXIS 3D to examine the installation influence on settlement reduction (ß), lateral displacement (U_x) and vertical displacement (U_z) relative to different values of lateral expansion of the column (0% to 15%).

The findings demonstrate the superior performance of GESC, particularly short columns outperforming floating counterparts. This enhanced performance is attributed to the combined effects of geosynthetic encasement and increased lateral expansion. Notably, these strategies contribute significantly to decreasing lateral displacement (U_x) at the column’s edge and reducing vertical displacement (U_z) under the rigid footing.

In contrast to previous studies that examined the installation effect of OSC contexts, this paper presents a comprehensive investigation into the effect of geosynthetic encasement and the installation effects using the lateral expansion method in very soft soil, using 3D numerical simulation. The study emphasizes the significance of the consideration of geosynthetic encasement and lateral expansion of the column during the design process to enhance column performance.