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This paper presents performance comparison of RF inductors with the same lateral geometry applying different substrate configurations. The purpose of presented research is to demonstrate and verify some advantages of low temperature co-fired ceramic (LTCC) technology in comparison to printed circuit board (PCB) technology based on the performance analysis of presented inductors in lower RF range.

The presented inductors are meander structures fabricated in LTCC and PCB technology, with same line width and outer dimensions. Performance analysis of all configurations is based on measurement results and numerical simulations. Advantage of LTCC technology is demonstrated by application of substrate pattering in order to maintain and/or improve expected inductor performances.

As expected, obtained results for the inductor with an air-gap show increase of the quality factor over 30 percent and widening of the operating frequency range by 50 percent when compared with the same LTCC structure without a gap. But what is more important the inductor with air-gap embedded inside LTCC stack maintains efficiency when compared to PCB inductor. This fact offers possibility of integration good quality components inside LTCC stack and reduction of used chip space.

Advantages of LTCC with respect to PCB design are demonstrated by efficiency increase of the proposed inductor configurations by means of design optimization relying on substrate pattering and incensement of the packaging density by embedding inductors. The presented findings are verified through consistency of measurement results and simulated data.

Strain gauges can be realised by printing and firing thick‐film resistors on ceramic substrates that are usually based on alumina. However, sensing elements made on some other substrates – tetragonal zirconia or stainless steel – would exhibit some improved characteristics, either due to a lower modulus of elasticity or a higher mechanical strength. As thick‐film resistors are developed for firing on alumina substrates their compatibility and possible interactions with other kinds of substrates have to be evaluated. The sheet resistivities and noise indices of the resistors were comparable, whereas the gauge factors were lower for the dielectric‐on‐steel substrates. The temperature coefficients of resistivity (TCR) of the resistors on the ZrO₂ and dielectric‐on‐steel substrates were higher than the TCRs on the alumina substrates, which was attributed to the higher thermal expansion coefficient of the tetragonal zirconia and the stainless steel.

The purpose of this paper is to demonstrate the influence of material properties and fabrication technique on the performance of an embedded pressure sensor. Based on conducted theoretical analysis a suitable material and technological technique that gave the best behavior of designed sensor was chosen for its fabrication. This is verified on the example of a resonant pressure sensor, designed for operation in the MHz range.

A sensor module is fabricated using the low temperature co‐fired ceramics (LTCC) technology and sputtering technique for electrodes deposition. The module comprises an inductor connected with a variable capacitor formed by the sensor membranes in a parallel LC circuit. An extensive parallel analysis of sensors performance for sensors with thick film (screen‐printed) and thin film (sputtered) electrodes is demonstrated. Mechanical and electrical parameters (Young's modulus and permittivity) of different tape materials that are considered for sensor fabrication are determined at room temperature.

Implementation of the sputtering technique for deposition of the thin film electrodes and usage of tapes with higher elasticity significantly contribute to the increase of the sensor performance (improved sensitivity) compared to designs found in available literature. Experimentally attained results are compared with the ones obtained by analytical calculations achieving good agreement of obtained results.

The improvement of sensor sensitivity by means of evaluation of different tape material and electrode thickness reduction is demonstrated for the first time. The presented results of the sensor equivalent model and the sensor‐antenna system are in good compliance with experimental data determined through measurement.

Failure analyses of the lead‐free and SnPb solder joints of high‐density packages such as the plastic ball grid array and the ceramic column grid array soldered on SnCu hot‐air solder levelling electroless nickel‐immersion gold or NiAu, and organic solderability preservative Entek printed circuit boards are presented. Emphasis is placed on determining the failure locations, failure modes, and intermetallic compound composition for these high‐density packages' solder joints after they have been through 7,500 cycles of temperature cycling. The present results will be compared with those obtained from temperature cycling and finite element analysis.

The lead‐free solder joint reliability of several printed circuit board mounted high‐density packages, when subjected to temperature cycling was investigated by finite element modelling. The packages were a 256‐pin plastic ball grid array (PBGA), a 388‐pin PBGA, and a 1657‐pin ceramic column grid array. Emphasis was placed on the determination of the creep responses (e.g. stress, strain, and strain energy density) of the lead‐free solder joints of these packages.

Temperature cycling tests, and statistical analysis of the results, for various high‐density packages on printed‐circuit boards with Sn‐Cu hot‐air solder levelling, electroless nickel‐immersion gold, and organic solder preservative finishes are investigated in this study. Emphasis is placed on the determination of the life distribution and reliability of the lead‐free solder joints of these high‐density package assemblies while they are subjected to temperature cycling conditions. A data acquisition system, the relevant failure criterion, and the data extraction method will be presented and examined. The life test data are best fitted to the Weibull distribution. Also, the sample mean, population mean, sample characteristic life, true characteristic life, sample Weibull slope, and true Weibull slope for some of the high‐density packages are provided and discussed. Furthermore, the relationship between the reliability and the confidence limits for a life distribution is established. Finally, the confidence levels for comparing the quality (mean life) of lead‐free solder joints of high‐density packages are determined.

The High Density Packaging Users Group conducted a substantial study of the solder joint reliability of high‐density packages using lead‐free solder. The design, material, and assembly process aspects of the project are addressed in this paper. The components studied include many surface mount technology package types, various lead, and printed circuit board finishes and paste‐in‐hole assembly.

Tests and analyzes a total quality management (TQM) methodology known as the mystery guest approach. The method involved the development of a research‐based approach to employee training by involving employees in the problem‐solving and strategic planning process. In this case study university student subjects were asked to participate in a focus group format which utilized the critical incidents, importance/performance analysis and planning effectiveness evaluation technique. Participants were organized to take a trip from Bowling Green, Ohio to Quebec City, Quebec with the itinerary including four major points of interest along the way and five on the return. Each point of interest was evaluated as a tourism experience for families. Findings revealed that participants developed their problem‐solving skills and improved their decision‐making abilities. It became apparent to the researchers that a research approach in training has the potential to be used in organizations to build employee loyalty, understanding and confidence.

This paper aims to discuss the importance, power, and significance of relationships and presence in non-directive group encounters for displaced children.

First, the importance of relationship in not only defining but also transforming “who we are” has been discussed. Then, the conditions that can be growth-promoting were explored.

Especially, a crucial element of growth-promoting group, i.e. presence, is discussed. The paper is concluded by discussing how these general techniques could be applied in the classroom.

Among the 7.6 million newly displaced people around the world in 2012, 46% of them are aged less than 18 years. This paper proves its importance for professionals working in academia or social work for developing a methodology to engage displaced youth in growth-promoting ways.

The purpose of this paper is to present a most accurate analytical model suit for the prediction of the elastic displacements in a ceramic strip for sensing longitudinal deformations. Accordingly, the objective of the analysis given is to develop a physically meaningful and simple‐as‐possible stress‐strain model for an elongated strip attached to a thick‐and‐stiff substrate.

Today's advanced strain gage designs intended for measuring deformations and related physical characteristics use sensitive elements manufactured as ceramic strips. The output signal depends to a great extent on the ability to measure and to adequately interpret the induced elastic displacements in the strip, as the global electric resistor is coupled strongly to the strain field in the sensitive layer. The dependence of the strain on the thickness of a strip is calculated using an analytical 2D stress‐strain model using a shear tension applied at its interface with the substrate and zero‐stress at the opposite face as boundary conditions. All necessary considerations and calculations to develop the model are discussed.

A significant result is the gradual reduction in the deformation depending on the layer thickness. Applying the model combines easy numerical effort with an expressive approximation.

The developed model can be used in the analysis and physical design of the structural elements of the type in question, not necessarily in the field of strain gage and sensor engineering.