Vilnius Gediminas Technical University
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Model for Elimination of Mixed Noise from MRI Heart Images
No full textA method for the preliminary processing of MRI images of the heart that allows for the elimination of fluctuation and impulse noise from useful signals is proposed. These types of noise are due to the regular geometric structure of the photoelectric elements of the MRI scanner matrix and the structure of the signal transmission channel. The aim of this work is to develop a comprehensive mathematical model for eliminating noise in the signal of an MRI scanner. In this work, mathematical models of linear and median filtering of impulse noise, fluctuation, and geometric noise are implemented. The mathematical models consist of the combined use of linear and median filters for recording MRI images of the heart. In the experiments, real MRI images of the heart from six patients with different diseases were used after noise was added to them. We were able to eliminate the impulse noise, geometric noise, and fluctuation noise in the MRI images by applying our filtering techniques. The filtering technique not only removed the noise, but also increased the contrast of the cancerous volumetric heterogeneous formations in the heart region.This article belongs to the Section Applied Biosciences and Bioengineerin
Text Augmentation Using BERT for Image Captioning
Get PDFImage captioning is an important task for improving human-computer interaction as well as for a deeper understanding of the mechanisms underlying the image description by human. In recent years, this research field has rapidly developed and a number of impressive results have been achieved. The typical models are based on a neural networks, including convolutional ones for encoding images and recurrent ones for decoding them into text. More than that, attention mechanism and transformers are actively used for boosting performance. However, even the best models have a limit in their quality with a lack of data. In order to generate a variety of descriptions of objects in different situations you need a large training set. The current commonly used datasets although rather large in terms of number of images are quite small in terms of the number of different captions per one image. We expanded the training dataset using text augmentation methods. Methods include augmentation with synonyms as a baseline and the state-of-the-art language model called Bidirectional Encoder Representations from Transformers (BERT). As a result, models that were trained on a datasets augmented show better results than that models trained on a dataset without augmentation.This article belongs to the Section Computing and Artificial IntelligenceThis research was funded by Google Cloud Platform Education Programs Grant
Analysis and improvement of multilingual speech coding
No full textDaktaro disertacijos santraukaDaktaro disertacijos santrauk
Modern Car Handbook
No full textThe handbook presents innovative technologies of a modern car. Cars with internal combustion
engines are mainly overviewed. Hybrid and electric vehicles are presented as well. Great
attention is paid to technologies that ensure fuel economy and reduction of gas emissions. The
newest internal combustion engine technology is presented and explained. The car passengers
and driver safety systems are widely considered. The assist and self-adaptive technology
principles for safely ride are reviewed and discussed too. Also, an introduction in the latest
technologies that help to protect the surrounding road users and particularly pedestrians is
delivered. Car security issues and some recommendations to protect your car from theft are
introduced. Car computers elements and its applications for car control and diagnosis are
examined. Widely and in details are discussed sensor system which applies in a modern car.
Sensors operation principles (physics) and technologies are studied and presented as well.Experimental Version.
Non-profit editio
Saccharomyces paradoxus Transcriptional Alterations in Cells of Distinct Phenotype and Viral dsRNA Content
Get PDFKiller yeasts are attractive antifungal agents with great potential applications in the food industry. Natural Saccharomyces paradoxus isolates provide new dsRNA-based killer systems available for investigation. The presence of viral dsRNA may alter transcriptional profile of S. paradoxus. To test this possibility, a high-throughput RNA sequencing was employed to compare the transcriptomes of S. paradoxus AML 15-66 K66 killer strains after curing them of either M-66 alone or both M-66 and L-A-66 dsRNA viruses. The S. paradoxus cells cured of viral dsRNA(s) showed respiration deficient or altered sporulation patterns. We have identified numerous changes in the transcription profile of genes including those linked to ribosomes and amino acid biosynthesis, as well as mitochondrial function. Our work advance studies of transcriptional adaptations of Saccharomyces spp. induced by changes in phenotype and set of dsRNA viruses, reported for the first time.This article belongs to the Special Issue Recent Advances in the Yeast Killer Systems ResearchThis research was partly funded by European Regional Funds (CZ.02.1.01/16_019/0000759)
Algorithm for Reducing Truck Noise on Via Baltica Transport Corridors in Lithuania
No full textThe section of Via Baltica going through the territory of the Republic of Lithuania is the most traffic intensive land logistics corridor in the country. The annual transportation volume has been increasing on this road; thus, the reduction of pollution caused by vehicles has become important. If gas emissions are regulated, and carriers have to pay pollution taxes, this does not apply to noise levels. The article presents the traffic intensity in this logistics corridor, measurements of the noise level at the characteristic points, its relation to the number of vehicles passing through it and an expert evaluation of proposed methods for noise energy reduction. Environmental noise is an unwanted or harmful sound that propagates in terms of both duration and geographical coverage. Noise is associated with many human activities, but road, rail and air traffic noises have the greatest impact. Due to irrationally arranged transport network, the transit flow of freight transport crosses residential areas of the city, places of rest and recreation of the population, causing high noise levels in adjacent areas. This is the biggest problem for the urban environment. Environmental noise affects many Europeans and is therefore considered by society to be one of the biggest environmental problems. This article presents an assessment of a new traffic noise algorithm. The presented expert survey on noise energy reduction allows choosing the most appropriate method for reducing noise energy in Via Baltica transport logistics corridor. Based on the expert survey, a hierarchical table for noise energy reduction was compiled. It will allow assessing the validity of individual noise energy reduction solutions. It has become relevant for improving infrastructure of other transport corridors and choosing the most appropriate solutions to reduce vehicle noise pollution. A further application of this model can be focused on economic evaluation, forecasting of expected benefits and so on.This article belongs to the Special Issue Uncertain Decision Making Methods in Energy Policies for Sustainable Developmen
Novel Microwave-Assisted Method of Y2Ti2O7 Powder Synthesis
No full textIn the paper, a novel technique for highly dispersed pyrochlore Y2Ti2O7 is proposed. The experimental results proved that the application of microwave irradiation at a certain stage of calcination allowed synthesizing of Y2Ti2O7 in much shorter time, which ensured substantial energy savings. An increase up to 98 wt.% in the content of the preferred phase with a pyrochlore-type structure Y2Ti2O7 was obtained after 25 h of yttrium and titanium oxides calcination at a relatively low temperature of 1150 °C, while the microwave-supported process took only 9 h and provided 99 wt.% of pyrochlore. The proposed technology is suitable for industrial applications, enabling the fabrication of large industrial amounts of pyrochlore without solvent chemistry and high-energy mills. It reduced the cost of both equipment and energy and made the process more environmentally friendly. The particle size and morphology did not change significantly; therefore, the microwave-assisted method can fully replace the traditional one.This article belongs to the Special Issue Advances in Materials ProcessingThis research was supported by Ministry of Education and Science of Ukraine, grant No. 0118U002026
“Physical Principles and Creation of Promising Composite Materials with Ultra- and Nanosized Oxides of New
Generation for Heavy Duty” and co-funded from the ‘Excellent science’ program of the Polish Ministry of Science
and Higher Education as a part of the contract No. DNK/SP/465641/2020 “The role of the agricultural engineering
and environmental engineering in the sustainable agriculture development.
Big Data Manifestation in Municipal Waste Management and Cryptocurrency Sectors: Positive and Negative Implementation Factors
No full textTwo mainstream topics have been widely discussed over the past few years: ways to reduce the human impact on nature and the way that the industrial revolution 4.0 changes industries. The aim of this research topic is to analyse the positive and negative factors of big data implementation in the sector of cryptocurrency (as part of the industrial revolution 4.0) and in the sector of municipal waste management. The analysis reveals the differences and similarities between the cryptocurrency and municipal waste management sectors in the context of big data. The findings are significant for the estimation of the technological development of digitalized and non-digitalized sectors.This research publishing was funded by VsI Solidarus
Mapping the Scientific Research on Mass Customization Domain: A Critical Review and Bibliometric Analysis
No full textResearchers of the Mass Customization domain face not only challenges of proper and timeless identification of latest practical trends, but also difficulties in rational analyses on the numerous existing scientific studies in this field as well as a need for a comprehensive and multidimensional state-of-the-art overview of the Mass Customization research domain in the last three decades. Therefore, the present research article aims to provide a critical standpoint and reveal the main research directions and content at systemic, bibliometric and historical research levels in the period of 1990–2020. Four types of bibliometric clustering techniques and a visualization of results in a format of two-dimensional maps by the VOSviewer software were applied in the analysis on 1783 scientific papers from the Clarivate Analytics Web of Science Core Collection. The analysis reveals six historical periods in the Mass Customization research domain, from which, in the last three decades, three are identified as influencing modern Mass Customization research areas and objects. Results confirmed a shift from a stand-alone scientific approach to the customization of tangible products in the manufacturing field and their risk management, to a hybrid scientific approach with a focus on the customization of non-tangible products and personalized customer behavior in online environments.This article belongs to the Special Issue Innovation, Internationalization and Entrepreneurshi
Multiple criteria model for reconstruction decisions selection of cultural heritage buildings
Get PDFDisertacijoje nagrinėjamos kultūros paveldo pastatų rekonstrukcijos ir tvarkybos darbų atlikimo problemos. Tyrimų objektas – kultūros paveldo pastatų rekonstrukcijos sprendiniai. Pagrindinis disertacijos tikslas – pasiūlyti daugiakriterį vertinimo modelį kultūros paveldo pastatų rekonstrukcijos darbams atlikti. Disertacijoje pritaikyti esami daugiakriteriai sprendimo priėmimo metodai bei pasiūlyti jų deriniai, siekiant tinkamai išsaugoti kultūros paveldo pastatus.
Disertaciją sudaro įvadas, trys skyriai, bendrosios išvados, naudotos literatūros ir autorės publikacijų disertacijos tema sąrašai bei priedai, susiję su disertacijos nagrinėjamomis temomis.
Įvadiniame skyriuje aptariama tiriamoji problematika, darbo aktualumas, aprašomas tyrimų objektas, formuluojamas darbo tikslas ir uždaviniai, darbų rezultatų praktinė reikšmė bei ginamieji teiginiai. Įvado pabaigoje pristatomi autorės pranešimai konferencijose ir publikacijos, pateikiama disertacijos struktūra.
Pirmajame skyriuje apžvelgiama kultūros paveldo samprata ir jo rekonstrukcijos analizė, 1993–2018 metų užsienio ir Lietuvos mokslinių publikacijų analizė, tyrinėjant kultūros paveldą. Nagrinėjama kultūros paveldo pastatų rekonstrukcijos darbų problematika: veiksnių, lemiančių kultūros paveldo pastatų rekonstrukciją, bei rekonstrukcijos metodų apžvalga. Skyriaus pabaigoje formuluojamos išvados bei tikslinami disertacijos uždaviniai.
Antrajame disertacijos skyriuje pateikiamas kultūros paveldo pastatų rekonstrukcijos darbų rodiklių sistemos sudarymas, paremtas Jungtinių Tautų švietimo, mokslo ir kultūros organizacijos UNESCO (angl. United Nations Educational, Scientific and Cultural Organization) teisės aktais ir Lietuvos teisės aktais bei atliktais moksliniais tyrimais. Apžvelgiamas daugiakriterių metodų parinkimas, skirtas kultūros paveldo pastatų rekonstrukcijos darbų daugiakriteriam modeliui.
Trečiajame skyriuje atliekamas kultūros paveldo projektų įgyvendinimo prioritetų rangavimas, taikant AHP ir EDAS metodus, parenkami rangovai, vykdant Lietuvos rusų dramos teatro ir Šv. Stepono bažnyčios sgrafito technikos tvarkybos darbus. Pirmajam rangovų atrankos procesui taikomas ekspertų vertinimas, AHP ir PROMETHEE metodas, antrajam – AHP, SWARA ir WASPAS-SVNS metodai. Pristatomas rodiklių parinkimas ir jų reikšmingumo nustatymas kultūros paveldo pastatų pritaikymui, taikant AHP metodą.
Svarbiausi tyrimų rezultatai paskelbti aštuoniose mokslinėse publikacijose ir aptarti keturiose mokslinėse konferencijose.Disertacij