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1 – 10 of 129Walter Gschohsmann, Johann Nicolics and Ephraim Suhir
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Originality/value
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.
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This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper…
Abstract
This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.
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This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder…
Abstract
This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.
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Discusses the 27 papers in ISEF 1999 Proceedings on the subject of electromagnetisms. States the groups of papers cover such subjects within the discipline as: induction machines;…
Abstract
Discusses the 27 papers in ISEF 1999 Proceedings on the subject of electromagnetisms. States the groups of papers cover such subjects within the discipline as: induction machines; reluctance motors; PM motors; transformers and reactors; and special problems and applications. Debates all of these in great detail and itemizes each with greater in‐depth discussion of the various technical applications and areas. Concludes that the recommendations made should be adhered to.
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P. Ohlckers, B. Sundby Avset, A. Bjorneklett, L. Evensen, J. Gakkestad, A. Hanneborg, T. Hansen, A. Kjensmo, E. Kristiansen, H. Kristiansen, H. von der Lippe, M. Nese, E. Nygård, F. Serck‐Hanssen and O. Søråsen
The Center for Industrial Research (SI), the University of Oslo (UiO) and a group of Norwegian companies have collaborated between 1990 and 1992 in the research programme…
Abstract
The Center for Industrial Research (SI), the University of Oslo (UiO) and a group of Norwegian companies have collaborated between 1990 and 1992 in the research programme ‘Industrial Microelectronics’ with a total cost of 30 MNOK. The programme was sponsored by the Norwegian Scientific and Industrial Research Council (NTNF) as one of the twin programmes constituting a national research initiative in microelectronics. The motivation for the programme is the recognition of microelectronics as a key technology commanding the performance and market success of many of the electronics systems from the Norwegian electronics industry towards the year 2000. The main objective is to stimulate industrial innovation by developing, transferring and exploiting knowledge and methods based upon advanced microelectronics. Focused activities are silicon sensor technology, combined analogue/digital design of application‐specific integrated circuits, large scale instrumentation, sensor packaging and thermal management of electronic systems. SI is focusing on applied research, UiO on education, and collaborating Norwegian companies are using the results in their own R&D projects. It is anticipated that the research results will be fully industrialised within 3–5 years. The programme is co‐ordinated with other Norwegian government‐sponsored research activities as well as European research programmes based on microelectronics. The programme is organised in projects and monitored with a set of milestones strongly indicating the achievement of successful industrial innovation, research results of international standing and high‐quality education of key personnel for the industry. Several successful examples of the research results are highlighted: Design and process methodology for double‐sided microstrip silicon radiation sensors for detection of high energy elementary particles, silicon‐to‐silicon and silicon‐to‐thin film anodic bonding processes for sensor fabrication, combined analogue/digital application‐specific integrated circuits for front‐end instrumentation applications, packaging of radiation sensors and thermal management of electronic systems by evaporation cooling. It is concluded that the programme has successfully achieved results in harmony with the objective.
Ceramic materials and glasses have become important in modern industry as well as in the consumer environment. Heat resistant ceramics are used in the metal forming processes or…
Abstract
Purpose
Ceramic materials and glasses have become important in modern industry as well as in the consumer environment. Heat resistant ceramics are used in the metal forming processes or as welding and brazing fixtures, etc. Ceramic materials are frequently used in industries where a wear and chemical resistance are required criteria (seals, liners, grinding wheels, machining tools, etc.). Electrical, magnetic and optical properties of ceramic materials are important in electrical and electronic industries where these materials are used as sensors and actuators, integrated circuits, piezoelectric transducers, ultrasonic devices, microwave devices, magnetic tapes, and in other applications. A significant amount of literature is available on the finite element modelling (FEM) of ceramics and glass. This paper gives a listing of these published papers and is a continuation of the author's bibliography entitled “Finite element modelling of ceramics and glass” and published in Engineering Computations, Vol. 16, 1999, pp. 510‐71 for the period 1977‐1998.
Design/methodology/approach
The form of the paper is a bibliography. Listed references have been retrieved from the author's database, MAKEBASE. Also Compendex has been checked. The period is 1998‐2004.
Findings
Provides a listing of 1,432 references. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.
Originality/value
This paper makes it easy for professionals working with the numerical methods with applications to ceramics and glasses to be up‐to‐date in an effective way.
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B.S. Hoffheins, R.J. Lauf and M.W. Siegel
An intelligent gas sensor has been developed using thick‐film techniques to create a semiconducting oxide surface with carefully varied catalytic properties. An integral heater…
Abstract
An intelligent gas sensor has been developed using thick‐film techniques to create a semiconducting oxide surface with carefully varied catalytic properties. An integral heater causes the surface to react with combustible gases and the resulting resistance map of the surface forms a signature that can be related to the functional groups present in the gas. For example, alcohols, ketones and alkanes have distinct, recognisable signatures on one sensor model.
Laura Jasińska, Krzysztof Szostak, Milena Kiliszkiewicz, Piotr Słobodzian and Karol Malecha
The main purpose of this study is to test the performance of the ink-jet printed microwave resonant circuits on Low temperature co-fired ceramics (LTCC) substrates combined with…
Abstract
Purpose
The main purpose of this study is to test the performance of the ink-jet printed microwave resonant circuits on Low temperature co-fired ceramics (LTCC) substrates combined with microfluidic channels for sensor applications. Normally, conductive patterns are deposited on an LTCC substrate by means of the screen-printing technique, but in this paper applicability of ink-jet printing in connection with LTCC materials is demonstrated.
Design/methodology/approach
A simple microfluidic LTCC sensor based on the microstrip ring resonator was designed. It was assumed the micro-channel, located under the ring, was filled with a mixture of DI water and ethanol, and the operating frequency of the resonator was tuned to 2.4 GHz. The substrate was fabricated by standard LTCC process, and the pattern of the microstrip ring resonator was deposited over the substrate by means of an ink-jet printer. Performance of the sensor was assessed with the use of various volumetric concentrations of DI water and ethanol. Actual changes in concentration were detected by means of microwave measurements.
Findings
It can be concluded that ink-jet printing is a feasible technique for fast fabrication of micro-strip circuits on LTCC substrates, including microfluidic components. Further research needs to be conducted to improve the reliability, accuracy and performance of this technique.
Originality/value
The literature shows the use of ink-jet printing for producing various conductive patterns in different applications. However, the idea to replace the screen-printing with the ink-jet printing on LTCC substrates in connection with microwave-microfluidic applications is not widely studied. Some questions concerning accuracy and reliability of this technique are still open.
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Zhou Gaofeng, Zhao Yulong and Jiang Zhuangde
The flexibly thin film grid pressure sensor is mainly used to detect the interface pressure distribution between touching objects. Aim at larger measurement error, the strip…
Abstract
Purpose
The flexibly thin film grid pressure sensor is mainly used to detect the interface pressure distribution between touching objects. Aim at larger measurement error, the strip double sensing layer pressure sensor are designed and fabricated and tested.
Design/methodology/approach
Defects and characteristic of the flexibly thin film grid pressure sensor based on piezoresistive effect are analyzed and pointed out in this paper. After comparison of four sensors, the strip double sensing layer pressure sensor was thought to be best.
Findings
Experiment shows that the strip double sensing layer pressure sensor could eliminate the measurement error basically and illustrates the validity of measuring the interface pressure distribution between area touching objects.
Research limitations/implications
In this paper, only the strip double sensing layer pressure sensor was used to verify the validity of measuring the static interface pressure distribution between peach and platform. But there also exists some problems such as the adhering reliability of electrode and the unevenness of sensing layer. These problems could be overcome in the future research if the fabricating procedure and ingredient of material could be adjusted correctly.
Practical implications
The strip double sensing layer pressure sensor could be applied to detect the static interface pressure distribution such as peach pressure distribution. For dynamic measurement, this research needs to be done further.
Originality/value
Strip double sensing layer pressure sensor with simple “interlayer” structure and with low manufacture cost is presented to basically eliminate the measurement error of interface pressure distribution of original sensor.
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