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Thick film superconductors with the nominal composition Bi2Pb0.5Sr2Ca2.5Cu3.5Ox were fired on stainless steel substrates and on alumina substrates covered with silver or gold thick film conductors. Films on stainless steel substrates were semiconducting due to reaction between the superconducting film and oxidised chromium and iron from the steel. Tc(R=0) of films on silver was between 80 K and 90 K while Tc (R=0) on gold was below 60 K. The low Tc (R=0) of films on gold is attributed to the interaction between the gold layer and copper from the superconductor.

A superconducting material with a composition Y1−xBa2Cu3O7−3/2x − x/2 Bi2O3 (x = 0·1 and 0·2) was synthesised. The influence of Bi2O3 additions on sintering was studied. Preliminary investigations of the Bi‐Sr‐Ca‐Cu‐O system were also made. Thick film pastes, prepared from Y1−xBixBa2Cu3O7 compositions, from the compound YBa2Cu3O7 with 10 w/o addition of Bi2CuO4 and from two compositions in the Bi‐Sr‐Ca‐Cu‐0 system, were fired on Al2O3 and ZrO2 substrates. All thick film materials based on YBa2Cu3O7 compound were superconducting at temperatures above 77 K when fired on ZrO2 substrates, while only a material with the starting composition Y0·8Ba2Cu3O6.7 − 0·1 Bi2O3 reached zero resistivity above 77 K on Al2O3 substrates. Tc (onset) of samples based on the YBa2Cu3O7 compound was around 95 K, and of samples from the Bi‐Sr‐Ca‐Cu‐O system between 95 and 100 K.

A superconducting material with the composition YBa1.8Pb0.2Cu3O7 was synthesised. The influence of PbO addition on the sintering and formation of the superconducting compound YBa2Cu3O7 was investigated. A thick film paste, prepared from prereacted material and an organic vehicle, was fired on Al2O3 and ZrO2 substrates. The resistivity of samples on ZrO2 substrates decreased to zero around 90 K, while samples on Al2O3 substrates did not reach zero resistivity until 77 K, which is probably due to the differences in thermal expansion coefficient between Al2O3 and the superconducting material. Interactions between Pt alloy based thick film conductors and superconducting material were studied.

Interactions between stainless steel and silver and gold based thick film conductors and YBa2Cu3O7 thick film superconductors were studied by SEM and EDX. The stainless steel reacted with the superconducting layer, forming a Ba‐Fe‐O compound on the interface, while BaO‐depleted YBa2Cu3O7 compound transformed into insulating Y2BaCuO5 compound. When YBa2Cu3O7 is fired on a gold thick film conductor, a thin layer of Y2BaCuO5 compound forms between the conductor and the superconducting film. In the case of a thin Ag conductor, BaO diffused through the silver film and reacted with alumina ceramic to the depth of a few μm. When a thicker silver layer (40–50 μm) was used, diffusion did not occur.

The main purpose of the expert system presented in the paper is to support proper decision-making to perform the operation of the complex and crucial technical system in a rational way.

The proposed system was developed using the universal concepts of a semi-Markov process, quality space and a multi-objective analysis. The maintenance and operation processes of a machine were modelled in the form of a semi-Markov process, the quality space was used to exclude the operation and maintenance process of critical quality and finally, thanks to implementation of a multi-objective analysis, the assessment system was build.

By generating each flow of the process, the expert system supports optimization of a technical system operation to choose the best maintenance strategy. Application of the expert system created based on a real industrial system is presented at the end of the paper.

The limitations of the proposed approach can be found in the parts of simulation and assessment. As the number of states to be taken into consideration increases, the time of calculation gets longer as well. As regards the assessment, ranges of the criteria argument have to be determined. Unfortunately, in some industrial systems, they are difficult to define or they are infinite and should be artificially limited.

The system provides three most important benefits as compared to other solutions. The first benefit is the system ability to make a choice of the best strategy from the perspective of the accepted criteria. The second advantage is the ability to choose the best operation and maintenance strategy from the point of view of a decision-maker. And the third is that the decision-maker can be completely sure that the chosen way of operation is not of critical quality.

The novelty of the proposed solution involves the system approach to the expert system design, thanks to the described procedure which is flexible and can be easily implemented in different technical systems which have a crucial impact on reliability and safety of their operation. It is the unique combination of probability-based simulation, multi-dimensional quality considerations and multi-objective analysis.

For thick film resistor materials with low sheet resistivity (less than 10 ohm/□) sheet resistivity increases with decreasing resistor length, when terminated with Pd alloy based conductors. This is due to the reaction of palladium from the thick film conductor and bismuth ruthenate (Bi2Ru2O7), which is the active phase in thick film resistor material. The experimental results indicate the formation of Pd/Bi solid solution on the interface between the conductor and resistor. Because of its higher specific resistivity, this layer functions as an additional source of resistivity.

To examine the relationship between self‐esteem and job performance using others' perceptions of self‐esteem and to examine agreement in ratings of self‐esteem across sources.

A sample of 143 sales representatives, 113 supervisors, 420 peers, 435 customers, and 510 family and friends completed Rosenberg's measure of self‐esteem and a measure of acquaintanceship. Peers and supervisors rated the subjects' job performance. Correlations and hierarchical regression were used to explore the relationships.

Customer, peer, and supervisor perceptions of subjects' self‐esteem related significantly to peer and supervisor performance ratings, whereas self and family/friends perceptions did not. There was limited support for the acquaintanceship effect (greater agreement across sources when familiarity is greater), while context affected agreement (same context sources had greater agreement).

The study highlights the importance of looking at an employee from a variety of perspectives. Also, training employees to develop self‐enhancing behaviors may enhance their outcomes. Finally, training raters that their perceptions of co‐workers' self‐esteem may influence evaluations of performance could reduce unconscious errors.

If this had been a traditional study measuring self‐esteem's impact on performance ratings, no significant relationships could have been reported since individuals' perceptions of their own self‐esteem were not valid predictors of performance ratings. It may be the individual's public self‐esteem (e.g. impression management skills) that influences performance ratings. In particular, workplace sources perceived high self‐esteem as being important to job performance. The validity of self‐esteem may be understated through reliance on the self‐report method alone.

The purpose of this paper is to determine the maintenance performance indicators (MPIs) which are significant for maintenance decision making in the apparel industry through an accurate maintenance performance measurement.

A quantitative research approach was followed. A questionnaire survey was used to collect the data which were evaluated based on Mean Weighted Rating and Relative Importance Index.

In total, 15 significant MPIs were determined which can directly affect maintenance decision making. A systematic approach was finally developed by allocating weightages for each critical MPI.

These results can be used to assist the decision-making process and as a performance measurement platform for maintenance management of the apparel industry.

The significance of maintenance has not been recognized and the value created through such massive efforts has remained hidden. Therefore, the need of adopting a performance-based approach for maintenance management in apparel industry exists. This research was aimed to provide a systematic approach to make decisions on maintenance management in the apparel industry in Sri Lanka.

The purpose of this paper is to study the multi-objective optimization design method of high-power high-frequency magnetic-resonance air-core transformer (ACT).

First, this paper studies the interleaved winding technology, the process of modeling and simulation, the calculation method of high-frequency loss of Litz wire and the design of magnetic shielding in detail. Second, the multi-objective optimization design process of high-frequency magnetic-resonance ACT is established by parametric scanning method and orthogonal experiment method.

An ACT model of 2 kV/100 kW/81.34 kHz was designed. The efficiency, weight power density and volume power density are 99.61%, 21.6 kW/kg and 5.1 kW/kg, respectively. Finally, the multi-physical field coupling simulation method is used to calculate the port excitation voltages and currents and temperature field of ACT. The maximum temperature of the ACT is 95.5 °C, which meets the design requirements.

The above research provides guidance and basis for the optimization design of high-power high-frequency magnetic-resonance ACT.

The purpose of this paper is to test a model in which instructor’s attributes (i.e. personality, age) are specified as social stimuli. Drawing on a constructivist view of learning (Palincsar, 1998) and similarity-attraction paradigm (Byrne, 1971), the authors hypothesize that instructor’s attributes influence learners’ reactions and dictate key attributions for learning: instructor’s competence and goodwill. The authors place these attributions as antecedents of learning results.

In a quasi-experimental design, undergraduate business students (n=133) participated in a training program of managerial skills over a three-week period. Regression and path analyses were utilized in testing the hypothesized model.

Results provide partial support to the hypothesized model and suggest that learning is a social event wherein learners’ attributions play a key role. Results also indicate that learner-instructor similarity in personality is an important antecedent of learners’ social reactions. The authors discuss how instructor’s attributes become social stimuli.

The authors address why the instructor’s personality might be more consequential for learning than his/her demographic attributes. Also, the authors discuss why the manipulation of learners’ attributions might be considered an appropriate pedagogical strategy.

Scholars primarily considered learners’ traits (e.g. IQ) and educational practices (e.g. teaching style) in explaining learning results. This emphasis has neglected analysis of the social role of instructors. This study contributes by examining how instructors induce social reactions on learners with significant repercussions for learning.