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1 – 10 of 11Miroslaw Górny, Artur Jazdon and Piotr Nowak
Reports the results of a survey rating the amount and degree of the utilisation of printed materials in Polish academic libraries. The results which are presented by type (for…
Abstract
Reports the results of a survey rating the amount and degree of the utilisation of printed materials in Polish academic libraries. The results which are presented by type (for example chemical, biological, technical libraries etc.) as well as by function (research libraries and libraries of educational institutions), concern the number of materials, including both books and periodicals. The authors include the amount of material in English as well as in other foreign languages. Figures illustrating the annual increase of these materials are also included. In addition, the article offers data which cover a number of issues, including the range of materials which were ordered at the request of users, the time of cataloguing, the number of loans, the number of unfilled orders, the extent of the utilisation of the collections, the number of interlibrary loans, as well as the relegation of outdated materials. Finally, the survey reveals information on the number of libraries which research into user needs, the number of libraries which are open on Saturdays and Sundays, and the number of libraries which provide special services such as weekend loans.
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Marcin Nowak, Marta Pawłowska-Nowak, Małgorzata Kokocińska and Piotr Kułyk
With the use of the grey incidence analysis (GIA), indicators such as the absolute degree of grey incidence (εij), relative degree of grey incidence (rij) or synthetic degree of…
Abstract
Purpose
With the use of the grey incidence analysis (GIA), indicators such as the absolute degree of grey incidence (εij), relative degree of grey incidence (rij) or synthetic degree of grey incidence (ρij) are calculated. However, it seems that some assumptions made to calculate them are arguable, which may also have a material impact on the reliability of test results. In this paper, the authors analyse one of the indicators of the GIA, namely the relative degree of grey incidence. The aim of the article was to verify the hypothesis: in determining the relative degree of grey incidence, the method of standardisation of elements in a series significantly affects the test results.
Design/methodology/approach
To achieve the purpose of the article, the authors used the numerical simulation method and the logical analysis method (in order to draw conclusions from our tests).
Findings
It turned out that the applied method of standardising elements in series when calculating the relative degree of grey incidence significantly affects the test results. Moreover, the manner of standardisation used in the original method (which involves dividing all elements by the first element) is not the best. Much more reliable results are obtained by a standardisation that involves dividing all elements by their arithmetic mean.
Research limitations/implications
Limitations of the conducted evaluation involve in particular the limited scope of inference. This is since the obtained results referred to only one of the indicators classified into the GIA.
Originality/value
In this article, the authors have evaluated the model of GIA in which the relative degree of grey incidence is determined. As a result of the research, the authors have proposed a recommendation regarding a change in the method of standardising variables, which will contribute to obtaining more reliable results in relational tests using the grey system theory.
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Piotr Furmański and Jerzy Banaszek
This paper aims to tackle the problem of some ambiguity of the momentum equation formulation in the commonly used macroscopic models of two‐phase solid/liquid region, developing…
Abstract
Purpose
This paper aims to tackle the problem of some ambiguity of the momentum equation formulation in the commonly used macroscopic models of two‐phase solid/liquid region, developing during alloy solidification. These different appearances of the momentum equation are compared and the issue is addressed of how the choice of the particular form affects velocity and temperature fields.
Design/methodology/approach
Attention is focused on the ensemble averaging method, which, owing to its stochastic nature, is a new promising tool for setting up the macroscopic transport equations in highly inhomogeneous multiphase micro‐ and macro‐structures, with morphology continuously changing in time when the solidification proceeds. The basic assumptions of the two other continuum models, i.e. based on the classical mixture theory and on the volume‐averaging technique, are also unveiled. These three different forms of the momentum equation are then compared analytically and their impact on calculated velocity and temperature distribution in the mushy zone is studied for the selected test problem of binary alloy solidification driven by diffusion and thermal natural convection in a square mould.
Findings
It is found that a chosen appearance of the momentum equation mildly affects temporal velocity/temperature, and shapes of the phase interface at longer times of the solidification.
Research limitations/implications
This mainly results from small variations of the liquid fraction across the mushy zone and from a low solidification rate, and it may change drastically when anisotropic properties of the mushy zone, solutal convection, different phase densities and cooling conditions are considered. Therefore, further comprehensive study is needed.
Originality/value
The paper addresses how the different focus of the momentum equation for liquid flow is compared.
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Robert Smoleński, Adam Kempski, Jacek Bojarski and Piotr Leżyński
The purpose of this paper is to evaluate the conditions in which a saturation of the common mode (CM) choke might appear to be essential for proper design of the CM voltage…
Abstract
Purpose
The purpose of this paper is to evaluate the conditions in which a saturation of the common mode (CM) choke might appear to be essential for proper design of the CM voltage filters. This paper presents a method for the determination of a CM choke flux density produced by multilevel inverters with carrier‐based modulations.
Design/methodology/approach
The proposed combination of secant and tangent methods allows efficient and high‐resolution determination of the CM voltage waveforms produced at the output of the multilevel inverters with commonly used carrier‐based modulations.
Findings
The presented results show that the application of a five‐level inverter with specific modulation causes a decrease of the maximum flux density, down to 15 per cent of the maximum level of the flux density reached in a two‐level inverter. The proposed, dedicated approximation method provides an accuracy of the root estimation better by about three orders for a comparable number of the function calls in comparison with Brent's method.
Practical implications
The presented theoretical evaluations make possible the determination of the maximum expected value of the flux density produced by multilevel inverters with various types of carrier‐based modulations, which allows a reduction in dimensions, weight and cost of CM chokes applied in CM voltage compensators.
Originality/value
In the paper, the new formulas that describe the placement of triangular carrier functions for commonly used multilevel inverters have been presented. In order to avoid accumulation of the estimation error, during determination of the CM voltage time integral, a dedicated, efficient method of roots approximation has been developed.
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Ron G. Christian, Samer N. Sarofim, Brian S. Gordon and Piotr S. Bobkowski
The purpose of this paper is to examine how exposure to a cause-related marketing (CRM) initiative involving sport teams affects attitude formation for the team and its…
Abstract
Purpose
The purpose of this paper is to examine how exposure to a cause-related marketing (CRM) initiative involving sport teams affects attitude formation for the team and its amplification of purchase intention for team-branded merchandise. Specifically, this paper assessed the role of distinct measures (warmth, brand attitude, admiration and success) on purchase intention.
Design/methodology/approach
The hypothesized model was tested using a 2 (promotion: CRM vs non-CRM) × 2 (team: successful vs unsuccessful) between-subjects design. Following MANCOVA analysis, the moderating effect of success was explored within the sequential moderated mediation model where perceived warmth and brand attitude explicated the effect of CRM exposure on purchase intention.
Findings
The results of this paper suggest that a “Warmth Effect” played a prominent role in shaping consumer perception for sports teams when partnered with a non-profit brand in a CRM appeal. Perceived team success was revealed as moderator, while warmth, brand attitude served as serial mediators on purchase intention.
Research limitations/implications
This paper provides evidence-based insights to sport marketers to leverage CRM strategy in strengthening brand-related outcomes. Sport marketers may find the CRM strategy useful for engaging “casual” fans. Further analysis is needed to determine the generalizability of this consumer response to CRM in other product domains.
Practical implications
Practical implications include leveraging CRM strategy to strengthen brand-related outcomes (i.e. perceived warmth, brand attitude and purchase intention), while also being mindful of the timing of CRM initiatives to optimize engagement. Sport marketers may find the CRM strategy useful for engaging “casual” fans.
Originality/value
This paper lends clarity to brand attitude formation in the context of CRM. The findings of this paper demonstrate the influence of perceived warmth, brand attitude and success on purchase intention.
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Piotr Grzybowski, Maciej Klimczuk and Pawel Rzucidlo
This paper aims to describe the idea behind and design of a miniaturized distributed measurement system based on a controller area network (CAN) data bus.
Abstract
Purpose
This paper aims to describe the idea behind and design of a miniaturized distributed measurement system based on a controller area network (CAN) data bus.
Design/methodology/approach
The intention of the designers was to build a light and modular measurement system which can be used in remotely piloted aircraft systems and ultra-light aircraft during flight tests, as well as normal operation. The structure of this distributed measurement system is based on a CAN data bus. The CAN aerospace standard has been applied to the software as well as the hardware comprising this system. PRP-W2 software designed for PCs is an additional component of the proposed measurement system. This software supports data acquisition from a recorder unit and allows for preliminary data analysis, as well as data conversion and presentation.
Findings
The system, complete with a high-speed data recorder, was successfully installed on board of an MP-02 Czajka aircraft. A research experiment using the system and oriented on airframe high frequency vibration analysis is presented in the final part of this paper.
Research limitations/implications
This measurement system allows analysis of high-frequency vibrations occurring at selected points of the aircraft. A data set is recorded by three-axis accelerometers and gyroscopes at frequencies up to 1 kHz.
Practical implications
The use of a miniature and lightweight modular measurement system will, in many cases, be faster and less expensive than full-scale measurement and data acquisition systems, which often require a lengthy assembly process. The implementation of this class of lightweight flight test systems has many advantages, in particular to the operation of small aircraft. Such solutions are likely to become increasingly common in unmanned aerial vehicles and in other light aircraft in the future.
Originality/value
The adaptation of a distributed measuring system with a high frequency of measurements for purposes of small and miniature aircraft.
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The purpose of this paper was to develop the methodology of thick-film/low temperature co-fired ceramic (LTCC) multilayer thermoelectric microgenerator fabrication including the…
Abstract
Purpose
The purpose of this paper was to develop the methodology of thick-film/low temperature co-fired ceramic (LTCC) multilayer thermoelectric microgenerator fabrication including the procedure of silver-nickel thermocouples integration with LTCC.
Design/methodology/approach
To miniaturize the structures and to increase the output parameters (generated voltage, electrical power), the microgenerator was designed as multilayer systems. It allows to reduce size of the system and to increase the number of thermocouples integrated inside the structure. It also protects buried thermocouples against exposure to harmful external factors (e.g. moisture, oxidation and mechanical exposures). As a substrate, LTCC was used. For the thermocouples fabrication, thick-film pastes based on silver and nickel were chosen. Ag/Ni thermocouple has nearly three times higher Seebeck coefficient and 30 per cent lower electrical resistance than the combination of Ag/PdAg used in previous works of the author.
Findings
A multi-layer thick-film thermoelectric generator based on LTCC and Ag, Ni pastes was fabricated. Thirty Ag/Ni thermocouples were precisely screen-printed on few layers. Thermocouples’ arms are 15 mm long and about 150 μm wide. Interlayer connections (via-holes filled with conductive paste) provided the electrical contact between the layers. The biggest fabricated harvester consisted of 90 miniature thermocouples buried inside the LTCC.
Originality/value
The paper presents the results of research that provided to optimize the co-firing process of the LTCC/Ni set. In the result, the methodology of co-firing of silver-nickel thermocouples and LTCC ceramic was elaborated. Also, the methodology of fabrication of miniature thermoelectric energy harvesters was optimized.
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The purpose of this paper is to investigate the possible application of thick‐film, metal‐based thermocouples to microsystems power supply. The subject of matter was development…
Abstract
Purpose
The purpose of this paper is to investigate the possible application of thick‐film, metal‐based thermocouples to microsystems power supply. The subject of matter was development of the procedure of thick‐film thermopile miniaturisation.
Design/methodology/approach
The aptitude of four photoimageable inks (based on silver or silver‐palladium) to fabrication of miniaturised thermocouples' arms was investigated. The object of interest was their compatibility with different kinds of low temperature cofired ceramic (LTCC) substrates, maximum resolution, shrinkage and electrical resistivity. Usage of the laser shaping technique to fabrication of narrow thermocouples' arms was also subject of matter. After tests and processes optimization both techniques were combined to fabricate the thick‐film Ag/Ni microthermopile.
Findings
Most of investigated inks were compatible with all tested LTCC tapes – fired as well as unfired (green tapes). Photoimageable inks technique can be successfully used for thermocouples' arms miniaturization. 40 μm/40 μm line/spaces resolution can be easily achieved. Combining this technique with laser shaping enabled microthermopile fabrication. It consisted of 42 Ag (photoimageable)/Ni (laser shaped) thermocouples. Arms width was 40 μm and 225 μm (Ag‐ and Ni‐arm, respectively), spaces between them – 65 μm. Overall, width of single thermocouple was smaller than 0.4 mm.
Practical implications
Fabrication of microthermopile consisting of several hundreds of thick‐film thermocouples will be possible if described procedure is applied. Such microgenerator will generate output power sufficient to supply some microsystems or microelectronic circuits.
Originality/value
The properties of four photoimageable inks were investigated as well as their compatibility with five different LTCC substrates (fired and unfired). Procedure of thick‐film microthermopile fabrication using photoimageable inks technique combined with laser shaping was proposed for the first time.
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Keywords
– The purpose of this work was fabrication of a small energy harvester.
Abstract
Purpose
The purpose of this work was fabrication of a small energy harvester.
Design/methodology/approach
The multilayer thermoelectric power generator based on thick-film and low temperature co-fired ceramic (LTCC) technology was fabricated. Precise paths printing method was used to fabricate Ag/Ni and Ag/PdAg thermocouples on a number of unfired LTCC tapes. The tapes were put together to form a multilayer stack. The via holes were used to make the electrical connections between adjacent layers. Finally, the multilayer stack was fired in the appropriate thermal profile.
Findings
It consists of 450 thermocouples and generates output voltage of about 0.45 V and output electrical power of about 0.13 mW when a temperature difference along the structure is 135°C. In the paper, individual stages of energy harvester fabrication process as well as its output parameters are presented.
Originality/value
Miniaturized thermoelectric energy harvester based on thick-film and LTCC technology was fabricated. As materials, metal-based pastes were used. This is the first paper where multilayer thermoelectric harvester, fabricated with the aid of LTCC technology, was described.
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Witold Nawrot and Karol Malecha
The purpose of this paper is to review possibilities of implementing ceramic additive manufacturing (AM) into electronic device production, which can enable great new…
Abstract
Purpose
The purpose of this paper is to review possibilities of implementing ceramic additive manufacturing (AM) into electronic device production, which can enable great new possibilities.
Design/methodology/approach
A short introduction into additive techniques is included, as well as primary characterization of structuring capabilities, dielectric performance and applicability in the electronic manufacturing process.
Findings
Ceramic stereolithography (SLA) is suitable for microchannel manufacturing, even using a relatively inexpensive system. This method is suitable for implementation into the electronic manufacturing process; however, a search for better materials is desired, especially for improved dielectric parameters, lowered sintering temperature and decreased porosity.
Practical implications
Relatively inexpensive ceramic SLA, which is now available, could make ceramic electronics, currently restricted to specific applications, more available.
Originality/value
Ceramic AM is in the beginning phase of implementation in electronic technology, and only a few reports are currently available, the most significant of which is mentioned in this paper.
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