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The purpose of this paper is to identify the productivity improvement potentials from maintenance planning practices in manufacturing companies. In particular, the paper aims at understanding the connection between machine criticality assessment and maintenance prioritization in industrial practice, as well as providing the improvement potentials.

An explanatory mixed method research design was used in this study. Data from literature analysis, a web-based questionnaire survey, and semi-structured interviews were gathered and triangulated. Additionally, simulation experimentation was used to evaluate the productivity potential.

The connection between machine criticality and maintenance prioritization is assessed in an industrial set-up. The empirical findings show that maintenance prioritization is not based on machine criticality, as criticality assessment is non-factual, static, and lacks system view. It is with respect to these finding that the ways to increase system productivity and future directions are charted.

In addition to the empirical results showing productivity improvement potentials, the paper emphasizes on the need for a systems view for solving maintenance problems, i.e. solving maintenance problems for the whole factory. This contribution is equally important for both industry and academics, as the maintenance organization needs to solve this problem with the help of the right decision support.

High-temperature (HT°) motors are made with inorganic coils wound with a ceramic-coated wire. They must be carefully designed because the HT° insulating materials have a lower breakdown voltages than the polymers used for insulating standard machines.

The voltage distribution between stator coils is computed with high-frequency (HF) equivalent circuits that consider the magnetic couplings and the stray capacitances. Two time scales are used for getting a fast computation of very short voltage spikes. For the first step, a medium time scale analysis is performed considering a simplified equivalent circuit made without any stray capacitance but with the full PWM pattern and the magnetic couplings. For the second step, a more detailed HF equivalent circuit computes voltage spikes during short critical time windows.

The computation made during the first step provides the critical time windows and the initial values of the state variables to the second one. The rise and fall time of the electronic switches have a minor influence on the maximum voltage stress. Conversely, the connection cable length and the common-mode capacitances have a large influence.

HF equivalent circuits cannot be used with random windings but only to formed coils that have a deterministic position of turns.

The proposed method can be used designing of HT° machine windings fed by PWM inverter and for improving the coils of standard machine used in aircraft’s low-pressure environments.

The influence of grounding system of the DC link is considered for computing the voltage spikes in the motor windings.

The progress of parallel computing in Information Retrieval (IR) is reviewed. In particular we stress the importance of the motivation in using parallel computing for text retrieval. We analyse parallel IR systems using a classification defined by Rasmussen and describe some parallel IR systems. We give a description of the retrieval models used in parallel information processing. We describe areas of research which we believe are needed.

The purpose of an electrical machines laboratory is (a) to provide the student with practical knowledge of the handling of electrical machines, (b) to correlate the theoretical classroom treatment with actual machine characteristics, (c) to demonstrate the most suitable testing techniques, and (d) to provide facilities for advanced work on machine operation and performance in integrated systems. Space and cost are usually of overriding importance, so great care is needed in the choice of suitable units and their layout in the laboratory, in order to achieve maximum efficiency of utilisation. Where possible, a machines laboratory should be used only for machines experiments, so that the most efficient layout for this purpose can be adopted without compromise.

This article reviews some of the more unconventional text retrieval systems, emphasising those which have been commercialised. These sophisticated systems improve on conventional retrieval by using either innovative software or hardware to increase retrieval speed or functionality, precision or recall. The software systems reviewed are: AIDA, CLARIT, Metamorph, SIMPR, STATUS/IQ, TCS, TINA and TOPIC. The hardware systems reviewed are: CAFS‐ISP, the Connection Machine, GESCAN,HSTS,MPP, TEXTRACT, TRW‐FDF and URSA.

Electrical machines are more and more fed by static converters. These power supplies impose nonsinusoidal statoric waveform to the machines. In these conditions, behaviour of magnetic material can be very different compared with sinusoidal ones. The characterization of magnetic material under non‐sinusoidal excitations is not clearly defined. At the present time, there is not any standard about operating test and specific parameters to be measured in order to get efficient knowledge of soft magnetic materials in distorted excitation mode. The aim of this paper is to present the effect of statoric connections on harmonic characterization parameters. The experimental results correspond to a Fe‐Si non oriented material excited by two different waveforms in a classical Epstein frame. The behaviour of the material is divided into two parts: the fundamental and the harmonic responses. The fundamental parameters are representative of the duty frequency of the machine, harmonic ones give information about additional losses; especially their harmonic distribution. They also allow us to estimate harmonic impact on the fundamental response.

Uninterruptible Power Supply (UPS) systems are typically designed to provide power to computers for five to thirty minutes after all utility company power has failed. In addition to providing blackout and brownout protection, many UPS systems also protect against spikes, surges, sags, and noise, and some also offer many of the features found in power distribution units (PDUs). The major components or subsystems of a typical UPS system are detailed, and a sample bid specification is appended. Three sidebars discuss UPSs and air conditioning, the maintenance bypass switch (MBS), and literature for further reading.

The purpose of this paper is to compare fundamental concepts from the grounded theory approach to social science research and concepts from entity‐relationship diagramming, a technique used to model data from the field of systems analysis, and propose that entity‐relationship diagramming can be a useful tool for grounded theory researchers.

The paper compares and contrasts concepts from the two different fields, demonstrating the construction of an entity‐relationship diagram from data from an existing grounded theory research project, and the correspondence between the data model constructs and the grounded theory constructs.

A strong correspondence was found between these two sets of concepts and suggests that the entity‐relationship diagramming technique may be a useful addition to the social scientist's toolkit when carrying out research using the grounded theory approach.

The paper bridges two distinct fields – information systems and grounded theory – and proposes a novel way for qualitative researchers to analyse and depict data.

The purpose of this article is to describe the design of electronic and microelectronic modules and, in particular, it focuses on connecting system of electrical modules to the main board of printed board. The theory of thermomechanical loading of system is presented. New methods of rigid solder connection for electronic modules are also presented.

A newly developed system with chip or cylindrical components is presented. The article describes a practical solution of connection with 0.603 and mini-metal electrode leadless face (MELF) surface mount device (SMD) resistors.

A new method of rigid solder connection for electronic modules is presented. This system is original and patented.

This solution is not used yet. Testing of a new system is executed now.

This article shows a real and original construction with chip and cylindrical chip components.