Nauki Techniczne

Metrology and Measurement Systems

Zawartość

Metrology and Measurement Systems | 2017 | vol. 24 | No 4 |

Abstrakt

Fault detection and location are important and front-end tasks in assuring the reliability of power electronic circuits. In essence, both tasks can be considered as the classification problem. This paper presents a fast fault classification method for power electronic circuits by using the support vector machine (SVM) as a classifier and the wavelet transform as a feature extraction technique. Using one-against-rest SVM and one-against-one SVM are two general approaches to fault classification in power electronic circuits. However, these methods have a high computational complexity, therefore in this design we employ a directed acyclic graph (DAG) SVM to implement the fault classification. The DAG SVM is close to the one-against-one SVM regarding its classification performance, but it is much faster. Moreover, in the presented approach, the DAG SVM is improved by introducing the method of Knearest neighbours to reduce some computations, so that the classification time can be further reduced. A rectifier and an inverter are demonstrated to prove effectiveness of the presented design.

Przejdź do artykułu

Abstrakt

The article presents state of work in technology of free-space optical communications (Free Space Optics − FSO). Both commercially available optical data links and their further development are described. The main elements and operation limiting factors of FSO systems have been identified. Additionally, analyses of FSO/RF hybrid systems application are included. The main aspects of LasBITer project related to such hybrid technology for security and defence applications are presented.

Przejdź do artykułu

Abstrakt

Basic gesture sensors can play a significant role as input units in mobile smart devices. However, they have to handle a wide variety of gestures while preserving the advantages of basic sensors. In this paper a user-determined approach to the design of a sparse optical gesture sensor is proposed. The statistical research on a study group of individuals includes the measurement of user-related parameters like the speed of a performed swipe (dynamic gesture) and the morphology of fingers. The obtained results, as well as other a priori requirements for an optical gesture sensor were further used in the design process. Several properties were examined using simulations or experimental verification. It was shown that the designed optical gesture sensor provides accurate localization of fingers, and recognizes a set of static and dynamic hand gestures using a relatively low level of power consumption.

Przejdź do artykułu

Abstrakt

The paper deals with evaluation of a 3D scanning method elaborated by the authors, by applying it to the analysis of the wear of forging tools. The 3D scanning method in the first place consists in the application of scanning to the analysis of changes in geometry of a forging tool by way of comparing the images of a worn tool with a CAD model or an image of a new tool. The method was evaluated in the context of the important measurement problems resulting from the extreme conditions present during the industrial hot forging processes. The method was used to evaluate wear of tools with an increasing wear degree, which made it possible to determine the wear characteristics in a function of the number of produced forgings. The following stage was the use it for a direct control of the quality and geometry changes of forging tools (without their disassembly) by way of a direct measurement of the geometry of periodically collected forgings (indirect method based on forgings). The final part of the study points to the advantages and disadvantages of the elaborated method as well as the potential directions of its further development.

Przejdź do artykułu

Abstrakt

Bluetooth beacons are becoming increasingly popular for various applications such as marketing or indoor navigation. However, designing a proper beacon installation requires knowledge of the possible sources of interference in the target environment. While theoretically beacon signal strength should decay linearly with log distance, on-site measurements usually reveal that noise from objects such as Wi-Fi networks operating in the vicinity significantly alters the expected signal range. The paper presents a novel mobile Geographic Information System for measurement, mapping and local as well as online storage of Bluetooth beacon signal strength in semireal time. For the purpose of on-site geovisual analysis of the signal, the application integrates a dedicated interpolation algorithm optimized for low-power devices. The paper discusses the performance and quality of the mapping algorithms in several different test environments.

Przejdź do artykułu

Abstrakt

The paper presents a method of adaptation of the original second order Prony’s method for applications in lowcost digital measurement systems with low computing performance. The presented method can be used in measuring systems where it is important to obtain in real time the values of amplitude, frequency, initial phase and damping coefficient of a single sinusoidal component of an analysed signal. The paper presents optimized, in terms of the number of mathematical operations, implementation of the method in selected embedded devices as well as the calculation times of the method for each platform.

Przejdź do artykułu

Abstrakt

Detection of leakages in pipelines is a matter of continuous research because of the basic importance for a waterworks system is finding the point of the pipeline where a leak is located and − in some cases − a nature of the leak. There are specific difficulties in finding leaks by using spectral analysis techniques like FFT (Fast Fourier Transform), STFT (Short Term Fourier Transform), etc. These difficulties arise especially in complicated pipeline configurations, e.g. a zigzag one. This research focuses on the results of a new algorithm based on FFT and comparing them with a developed STFT technique. Even if other techniques are used, they are costly and difficult to be managed. Moreover, a constraint in the leak detection is the pipeline diameter because it influences accuracy of the adopted algorithm. FFT and STFT are not fully adequate for complex configurations dealt with in this paper, since they produce ill-posed problems with an increasing uncertainty. Therefore, an improved Tikhonov technique has been implemented to reinforce FFT and STFT for complex configurations of pipelines. Hence, the proposed algorithm overcomes the aforementioned difficulties due to applying a linear algebraic approach.

Przejdź do artykułu

Abstrakt

Polymer-based capacitive humidity sensors emerged around 40 years ago; nevertheless, they currently constitute large part of sensors’ market within a range of medium (climatic and industrial) humidity 20−80%RH due to their linearity, stability and cost-effectiveness. However, for low humidity values (0−20%RH) that type of sensor exhibits increasingly nonlinear characteristics with decreasing of humidity values. This paper presents the results of some experimental trials of CMOS polymer-based capacitive humidity sensors, as well as of modelling the behaviour of that type of sensor. A logarithmic functional relationship between the relative humidity and the change of sensor output value at low humidity is suggested.

Przejdź do artykułu

Abstrakt

A developed method and measurement setup for measurement of noise generated in a supercapacitor is presented. The requirements for noise data recording are considered and correlated with working modes of supercapacitors. An example of results of low-frequency noise measurements in commercially available supercapacitors are presented. The ability of flicker noise measurements suggests that they can be used to assess quality of tested supercapacitors.

Przejdź do artykułu

Abstrakt

A complex model of mechanically ventilated ARDS lungs is proposed in the paper. This analogue is based on a combination of four components that describe breathing mechanics: morphology, mechanical properties of surfactant, tissue and chest wall characteristics. Physical-mathematical formulas attained from experimental data have been translated into their electrical equivalents and implemented in MultiSim software. To examine the adequacy of the forward model to the properties and behaviour of mechanically ventilated lungs in patients with ARDS symptoms, several computer simulations have been performed and reported in the paper. Inhomogeneous characteristics observed in the physical properties of ARDS lungs were mapped in a multi-lobe model and the measured outputs were compared with the data from physiological reports. In this way clinicians and scientists can obtain the knowledge on the moment of airway zone reopening/closure expressed as a function of pressure, volume or even time. In the paper, these trends were assessed for inhomogeneous distributions (proper for ARDS) of surfactant properties and airway geometry in consecutive lung lobes. The proposed model enables monitoring of temporal alveolar dynamics in successive lobes as well as those occurring at a higher level of lung structure organization, i.e. in a point P0 which can be used for collection of respiratory data during indirect management of recruitment/de-recruitment processes in ARDS lungs. The complex model and synthetic data generated for various parametrization scenarios make possible prospective studies on designing an indirect mode of alveolar zone management, i.e. with

Przejdź do artykułu

Abstrakt

Graphene is a very promising material for potential applications in many fields. Since manufacturing technologies of graphene are still at the developing stage, low-frequency noise measurements as a tool for evaluating their quality is proposed. In this work, noise properties of polymer thick-film resistors with graphene nano-platelets as a functional phase are reported. The measurements were carried out in room temperature. 1/f noise caused by resistance fluctuations has been found to be the main component in the specimens. The parameter values describing noise intensity of the polymer thick-film specimens have been calculated and compared with the values obtained for other thick-film resistors and layers used in microelectronics. The studied polymer thick-film specimens exhibit rather poor noise properties, especially for the layers with a low content of the functional phase.

Przejdź do artykułu

Abstrakt

The paper reports on a long-wave infrared (cut-off wavelength ~ 9 μm) HgCdTe detector operating under nbiased condition and room temperature (300 K) for both short response time and high detectivity operation. The ptimal structure in terms of the response time and detectivity versus device architecture was shown. The response time of the long-wave (active layer Cd composition, xCd = 0.19) HgCdTe detector for 300 K was calculated at a level of τs ~ 1 ns for zero bias condition, while the detectivity − at a level of D* ~ 109 cmHz1/2/W assuming immersion. It was presented that parameters of the active layer and P+ barrier layer play a critical role in order to reach τs ≤ 1 ns. An extra series resistance related to the processing (RS+ in a range 5−10 Ω) increased the response time more than two times (τs ~ 2.3 ns).

Przejdź do artykułu

Abstrakt

In the age of digital media, delivering broadcast content to customers at an acceptable level of quality is one of the most challenging tasks. The most important factor is the efficient use of available resources, including bandwidth. An appropriate way of managing the digital multiplex is essential for both the economic and technical issues. In this paper we describe transmission quality measurements in the DAB+ broadcast system. We provide a methodology for analysing parameters and factors related with the efficiency and reliability of a digital radio link. We describe a laboratory stand that can be used for transmission quality assessment on a regional and national level.

Przejdź do artykułu

Redakcja

Editor-in-Chief
  • Janusz SMULKO, Gdańsk University of Technology, Poland
International Programme Committee
  • Andrzej ZAJĄC, Chairman, Military University of Technology, Poland
  • Bruno ANDO, University of Catania, Italy
  • Martin BURGHOFF, Physikalisch-Technische Bundesanstalt, Germany
  • Marcantonio CATELANI, University of Florence, Italy
  • Numan DURAKBASA, Vienna University of Technology, Austria
  • Domenico GRIMALDI, University of Calabria, Italy
  • Laszlo KISH, Texas A&M University, USA
  • Eduard LLOBET, Universitat Rovira i Virgili, Tarragona, Spain
  • Alex MASON, Liverpool John Moores University, The United Kingdom
  • Subhas MUKHOPADHYAY, Massey University, Palmerston North, New Zealand
  • Janusz MROCZKA, Wrocław University of Technology, Poland
  • Antoni ROGALSKI, Military University of Technology, Poland
  • Wiesław WOLIŃSKI, Warsaw University of Technology, Poland
Associate Editors
  • Zbigniew BIELECKI, Military University of Technology, Poland
  • Vladimir DIMCHEV, Ss. Cyril and Methodius University, Macedonia
  • Krzysztof DUDA, AGH University of Science and Technology, Poland
  • Janusz GAJDA, AGH University of Science and Technology, Poland
  • Teodor GOTSZALK, Wrocław University of Technology, Poland
  • Ireneusz JABŁOŃSKI, Wrocław University of Technology, Poland
  • Piotr JASIŃSKI, Gdańsk University of Technology, Poland
  • Piotr KISAŁA, Lublin University of Technology, Poland
  • Manoj KUMAR, University of Hyderabad, Telangana, India
  • Grzegorz LENTKA, Gdańsk University of Technology, Poland
  • Czesław ŁUKIANOWICZ, Koszalin University of Technology, Poland
  • Rosario MORELLO, University Mediterranean of Reggio Calabria, Italy
  • Fernando PUENTE LEÓN, University Karlsruhe, Germany
  • Petr SEDLAK, Brno University of Technology, Czech Republic
  • Hamid M. SEDIGHI, Shahid Chamran University of Ahvaz, Ahvaz, Iran
  • Roman SZEWCZYK, Warsaw University of Technology, Poland
Language Editors
  • Andrzej Stankiewicz, Gdańsk University of Technology, Poland
Technical Editors
  • Agnieszka Kondratowicz, Gdańsk University of Technology, Poland

Kontakt

Editorial Office of Metrology and Measurement Systems

Contact:
E-mail: metrology@pg.edu.pl
URL: www.metrology.pg.gda.pl
Phone: (+48) 58 347-1357

Post address:
Editorial Office of Metrology and Measurement Systems
Gdańsk University of Technology, Faculty of Electronics, Telecommunications and Informatics

Instrukcje dla autorów

Types of contributions

The following types of papers are published in Metrology and Measurement Systems:
•    invited review papers presenting the current stage of the knowledge (max. 20 edited pages, 3000 characters each),
•    research papers reporting original scientific or technological advancements (10‒12 pages),
•    papers based on extended and updated contributions presented at scientific conferences (max. 12 pages),
•    short notes, i.e. book reviews, conference reports, short news (max. 2 pages).

Manuscript preparation

The text of a manuscript should be written in clear and concise English. The form similar to “camera-ready” with an attached separate file – containing illustrations, tables and photographs – is preferred. For the details of the preferred format of the manuscripts, Authors should consult a recent issue of the journal or the sample article and the guidelines for manuscript preparation. The text of a manuscript should be printed on A4 pages (with margins of 2.5 cm) using a font whose size is 12 pt for main text and 10 pt for the abstract; an even number of pages is strongly recommended. The main text of a paper can be divided into sections (numbered 1, 2, ...), subsections (numbered 1.1., 1.2., ...) and – if needed – paragraphs (numbered 1.1.1., 1.1.2., ...). The title page should include: manuscript title, Authors’ names and affiliations with e-mail addresses. The corresponding Author should be identified by the symbol of an envelope and phone number. A concise abstract of approximately 100 words and with 3–5 keywords should accompany the main text.
Illustrations, photographs and tables provided in the camera-ready form, suitable for reproduction (which may include reduction) should be additionally submitted one per page, larger than final size. All illustrations should be clearly marked on the back with figure number and author’s name. All figures are to have captions. The list of figures captions and table titles should be supplied on separate page. Illustrations must be produced in black ink on white paper or by computer technique using the laser printer with the resolution not lower than 300 dpi, preferably 600 dpi. The thickness of lines should be in the range 0.2–0.5 mm, in particular cases the range 0.1–1.0 mm will be accepted. Original photographs must be supplied as they are to be reproduced (e.g. black and white or colour). Photocopies of photographs are not acceptable.
References should be inserted in the text in square brackets, e.g. [4]; their list numbered in citation order should appear at the end of the manuscript. The format of the references should be as follows: for a journal paper – surname(s) and initial(s) of author(s), year in brackets, title of the paper, journal name (in italics), volume, issue and page numbers. The exemplary format of the references is available at the sample article.

Manuscript submission and processing

Submission procedure. Manuscript should be submitted via Internet Editorial System (IES) ‒ an online submission and peer review system http://www.editorialsystem.com/mms
In order to submit the manuscript via IES, the authors (first-time users) must create an author account to obtain a user ID and password required to enter the system. From the account you create, you will be able to monitor your submission and make subsequent submissions.
The submission of the manuscript in two files is preferred: “Paper File” containing the complete manuscript (with all figures and tables embedded in the text) and “Figures File” containing illustrations, photographs and tables. Both files should be sent in DOC and PDF format as well as. In the submission letter or on separate page in “Figures File”, the full postal address, e-mail and phone numbers must be given for all co-authors. The corresponding Author should be identified.
Copyright Transfer. The submission of a manuscript means that it has not been published previously in the same form, that it is not under consideration for publication elsewhere, and that – if accepted – it will not be published elsewhere. The Author hereby grants the Polish Academy of Sciences (the Journal Owner) the license for commercial use of the article according to the Open Access License which has to be signed before publication.
Review and amendment procedures. Each submitted manuscript is subject to a peer-review procedure, and the publication decision is based on reviewers’ comments; if necessary, Authors may be invited to revise their manuscripts. On acceptance, manuscripts are subject to editorial amendment to suit the journal style.
An essential criterion for the evaluation of submitted manuscripts is their potential impact on the scientific community, measured by the number of repeated quotations. Such papers are preferred at the evaluation and publication stages.
Proofs. Proofs will be sent to the corresponding Author by e-mail and should be returned within 48 hours of receipt.

Other information

Author Benefits. The publication in the journal is free of charge. A sample copy of the journal will be sent to the corresponding Author free of charge.
Colour. For colour pages the Authors will be charged at the rate of 160 PLN or 80 EUR per page. The payment to the bank account of main distributor must be acquitted before the date pointed to Authors by Editorial Office.

Ta strona wykorzystuje pliki 'cookies'. Więcej informacji