Vilnius Gediminas Technical University
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The First Application of Nanoelectrochemotherapy in Feline Oral Malignant Melanoma Treatment—Case Study
No full textThe aim of this study was to present the first domestic animal trial of nanosecond electroporation with chemotherapy and CO2 laser surgery. Methods: sixteen-year-old domestic cat with diagnosed melanoma on oral cavity was the case used in the study. Firstly, CO2 laser surgery was used for the removal of most of tumor mass. Then nanoelectrochemotherapy with bleomycin was applied including appropriate margin of healthy tissue. A 15 ± 4 kV/cm × 15 ns pulsing protocol was employed with a total of 800 ± 100 pulses. Only one session of nanoelectrochemotherapy (nanoECT) was performed. Results and conclusions: during the next two weeks areas of focal necrosis were replaced by the granulation tissue. Complete wound healing was observed four weeks after initial treatment. After 15 weeks post treatment, no local recurrence was apparent.This article belongs to the Special Issue Spontaneous Neoplasms in AnimalsThe research was supported by National Science Centre (Poland) within a framework of SONATA BIS 6
2016/22/E/NZ5/00671; PI: J. Kulback
Pinpointing the Barriers to Recycling at Destination
No full textThis paper aims to gain further understanding of the barriers that prevent tourists at tourist destinations from recycling. Methodologically, a survey was carried out with a questionnaire, reaching 371 units through a convenience sampling procedure on the island of Gran Canaria. The measuring instruments consisted of a Likert ‘beliefs’ scale, comprising statements related to a wide range of recycling barriers, as well as both sociodemographic and situational information. Firstly, we performed an exploratory factor analysis on the barriers scale, and several obstacles to recycling were identified, such as a lack of knowledge and familiarity, blaming of the system of collection, assumed incompatibility with a relaxing holiday, erroneous beliefs about environmental usefulness, disregard towards the place being visited and a certain sense of detachment, the non-existence of incentives, and an unwillingness to comply with perceived demands. Secondly, by means of ANOVA tests, we measured the causal relationship between these barriers to recycling and the tourists’ sociodemographic and situational profiles. The practical implications shed light on how to overcome the difficulties that occur for the tourist at the destination with regards to recycling, by considering the tourists’ beliefs and their sociodemographic and situational background.This article belongs to the Special Issue Optimal Tourism DevelopmentThis research received no external funding, but the principal author is involved in the Soclimpact project.
This project subject matter consists of fighting against Climate Change in the Islands and has received funding
from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 776661
Improving Safety of Transportation of Dangerous Goods by Railway Transport
No full textThe transport of dangerous goods by rail carries a high risk of accident and every effort should be made to ensure that such transport is carried out under the best possible safety conditions. The research objective was to analyze and identify the main risks associated with the transport of dangerous goods by rail as well as to identify and assess the main factors of safe transport in order to reduce the risk of accident. For this purpose, analysis of the literature, systematization, generalization, and evaluation by experts was applied. The article states that in order to ensure the safe transport of dangerous goods by rail, it is necessary to comply with the rules for loading and unloading dangerous goods, the established requirements and instructions, and technical conditions of wagons and their labelling as well as preventive measures to reduce the risk. Recommendations are provided on how to reduce accidents and incidents in the transport of dangerous goods by rail
Analyzing the Status of Sustainable Development in the Manufacturing Sector Using Multi-Expert Multi-Criteria Fuzzy Decision-Making and Integrated Triple Bottom Lines
No full textA sustainable manufacturing company depends on the developments in three aspects in order to minimize harmful impacts on the environment, improve the social relations, and simultaneously maximize the economic benefits. Despite the increasing types of investigations that researchers have carried out in environmental and economic aspects, the minimum attention has been paid to social relations. In response to this deficiency, this paper proposes a new framework to obtain the overall sustainability index in manufacturing companies by encapsulating the sustainability criteria/sub-criteria. This article collected 33 sub-criteria for five pillars of sustainability as social, environment, economic, technological advancement, and performance management. The key contributions of this paper are highlighted as the hierarchical method that obtains the status of sustainability in uncertain conditions, the ability to identify the weak points, and a new framework for gathering the data about sustainability performance in manufacturing companies. The findings of this paper will aid both policymakers and decision-makers to assess the sustainability status of manufacturing systems and improve the performances of them.This article belongs to the Special Issue Health Environment and Sustainable DevelopmentThe work was supported by the European Union’s Horizon 2020 project H2020-MSCA-RISE-2014 CLUSDEVMED Grant No. 64573073
Reduced-Reflection Multilayer PCB Microstrip with Discontinuity Characterization
No full textIn the era of technology and communication, printed circuit boards (PCBs) can be found in a myriad of devices—from ordinary household items, to state of the art custom metrology equipment. Different types of component for wireless communications are available and come in various packages, supplied by multiple manufacturers. The signal landpads for some high-frequency connectors and components, encapsulated in larger packages, are usually wider than the controlled impedance trace, thereby introducing unwanted impedance mismatch and resulting in signal reflections. The component land pad and microstrip width a discrepancy issue can be found in both complex high-density industrial devices and system-level academic research papers. This paper addresses the topic of compensating discontinuities, introduced by signal pads, which are wider than the target impedance microstrip, characterizes the difference between the compensated and uncompensated microstrip with discontinuity, and proposes a generalized guideline on compensating for the introduced impedance change in multilayer PCBs. The compensation method is based upon carefully designing the stackup of the PCB allowing for a reference plane cutout under the discontinuity to even out the impedance mismatch. A 6-layer PCB with IT180A dielectric material containing three structures has been manufactured and characterized using an Agilent E8363B vector network analyzer (VNA). A 4–12 dB improvement in S11 response in the whole frequency range up to 10 GHz, compared to that when no compensation has been applied, was observedThis article belongs to the Section Circuit and Signal Processin
Improvement of Diagnostic Parameters of a Rolling Wheel with Flat Spot and Experimental Test on Lithuanian Railways
No full textThe JSC (Joint-Stock Company) “Railway Products Conformity Assessment Center”, under a contract with JSC “Lithuanian Railways”, carried out a rolling stock geometry and rolling surface defect risk assessment study which analyzed the principles and algorithm of the ATLAS-LG system used by JSC “Lithuanian Railways” and the system’s advantages and similarities with other systems used for rolling surface defect prediction worldwide. According to the results of this study, JSC “Voestalpine VAE Legetecha” made changes to the algorithms of its ATLAS-LG computing system and changed the parameter used to determine the damage to wheelsets. The goal of this work was to review the automatic systems of rolling stock used to evaluate the state of the rolling stock, compare the criteria for culling, describe the methodology for setting a new parameter for detecting wheel damage Pderivative instead of the previous parameter Kdm, and upgrade operational algorithms of ATLAS. This paper describes the algorithm and methodology for setting a new parameter, evaluating the construction of rolling stock and movement speed. To develop a replacement algorithm for the ATLAS-LG system, a new parameter verification methodology using the inverse Laplace transform for the mathematical model was used.The research was funded by the Vilnius Gediminas Technical University (VGTU)
Research of Wood Waste as a Potential Filler for Loose-Fill Building Insulation: Appropriate Selection and Incorporation into Polyurethane Biocomposite Foams
No full textCurrently, the recycling potential of wood waste (WW) is still limited, and in a resource efficiency approach, recycling WW in insulation materials, such as polyurethane (PUR), appears as an appropriate solution. It is known that the quality of WW is the main aspect which influences the stability of the final products. Therefore, the current study analyses different WW-based fillers as possible modifiers for polyurethane biocomposite foams for the application as loose-fill materials in building envelopes. During the study of WW-based fillers, it was determined that the most promising filler is wood scobs (WS) with a thermal conductivity of 0.0496 W/m·K, short-term water absorption by partial immersion—12.5 kg/m2, water vapour resistance—0.34 m2·h·Pa/mg and water vapour diffusion resistance factor—2.4. In order to evaluate the WS performance as a filler in PUR biocomposite foams, different ratios of PUR binder and WS filler (PURb/WS) were selected. It was found that a 0.40 PURb/WS ratio is insufficient for the appropriate wetting of WS filler while a 0.70 PURb/WS ratio produced PUR biocomposite foams with the most suitable performance: thermal conductivity reduced from 0.0523 to 0.0476 W/m·K, water absorption—from 5.6 to 1.3 kg/m2, while the compressive strength increased from 142 to 272 kPa and the tensile strength increased from 44 to 272 kPa.This article belongs to the Special Issue Performance Research of Polyurethane Foams and Composite
Development of microsecond magnetic pulse generators for cell membrane permeabilization control
No full textDisertacijoje nagrinėjami magnetinio lauko impulsų generatoriai ir technologijos, skirtos valdyti ląstelės plazminės membranos pralaidumą. Naudojant impulsinius induktorius kaip apkrovą, disertacijoje buvo bandoma bekontktiniu būdu indukuoti grįžtamus ir negrįžtamus pokyčius biologiniuose objektuose, apžvelgiamos sukuriamo magnetinio lauko impulsų poveikio priklausomybės nuo impulso formos ir kitų parametrų.
Disertaciją sudaro įvadas, trys skyriai, bendrosios išvados, naudotos literatūros ir autoriaus publikacijų disertacijos tema sąrašai.
Įvadiniame skyriuje aptariama tiriamoji problema, darbo aktualumas, aprašomas tyrimų objektas, formuluojamas darbo tikslas bei uždaviniai, aprašoma tyrimų metodika, darbo mokslinis naujumas, darbo rezultatų praktinė reikšmė, ginamieji teiginiai. Įvado pabaigoje pristatomos disertacijos tema autoriaus paskelbtos publikacijos ir pranešimai konferencijose bei disertacijos struktūra.
Pirmasis skyrius skirtas literatūros apžvalgai. Jame analizuojami įvairių generatorių schemų veikimo principai ir pritaikymas. Skyriaus pabaigoje formuluojamos išvados ir tikslinami disertacijos uždaviniai.
Antrajame skyriuje aprašomi Markso topologijos, ignitrono ir tiristorių pagrindu sukurti magnetinio lauko generatoriai bei apžvelgiami atskirų grandinių veikimo principai.
Trečiajame skyriuje pateikti induktorių imitacinių modelių tyrimo rezultatai, indukuoto elektrinio lauko parametrai bei taikomųjų eksperimentų rezultatai su skirtingų tipų ląstelėmis.
Disertacijos tema paskelbti 5 straipsniai: keturi – moksliniuose žurnaluose, įtrauktuose į Clarivate Analytics Web of Science sąrašą, turinčiuose citavimo indeksą, vienas – konferencijų medžiagoje, įtrauktoje į Clarivate Analytics Web of Science duomenų bazę. Disertacijos tema perskaityti 8 pranešimai nacionalinėse bei tarptautinėse konferencijose.Daktaro disertacij
Investigation of Dual-Flow Deep Learning Models LSTM-FCN and GRU-FCN Efficiency against Single-Flow CNN Models for the Host-Based Intrusion and Malware Detection Task on Univariate Times Series Data
Full text linkIntrusion and malware detection tasks on a host level are a critical part of the overall information security infrastructure of a modern enterprise. While classical host-based intrusion detection systems (HIDS) and antivirus (AV) approaches are based on change monitoring of critical files and malware signatures, respectively, some recent research, utilizing relatively vanilla deep learning (DL) methods, has demonstrated promising anomaly-based detection results that already have practical applicability due low false positive rate (FPR). More complex DL methods typically provide better results in natural language processing and image recognition tasks. In this paper, we analyze applicability of more complex dual-flow DL methods, such as long short-term memory fully convolutional network (LSTM-FCN), gated recurrent unit (GRU)-FCN, and several others, for the task specified on the attack-caused Windows OS system calls traces dataset (AWSCTD) and compare it with vanilla single-flow convolutional neural network (CNN) models. The results obtained do not demonstrate any advantages of dual-flow models while processing univariate times series data and introducing unnecessary level of complexity, increasing training, and anomaly detection time, which is crucial in the intrusion containment process. On the other hand, the newly tested AWSCTD-CNN-static (S) single-flow model demonstrated three times better training and testing times, preserving the high detection accuracy.This article belongs to the Special Issue Machine Learning for Cybersecurity Threats, Challenges, and Opportunitie
Power Market Formation for Clean Energy Production as the Prerequisite for the Country’s Energy Security
No full textThe paper analyzes the main issues of power market development for clean energy production within the broader framework of ensuring the country’s energy security. In addition, special attention is paid to the technologies aimed at reducing emissions of toxic substances and greenhouse gases by the fossil-fired power plants. Even though the future electricity markets would most likely depend on the high shares of renewable energy sources (RES) in the electricity system, energy efficiency such as the one based on the near-zero emission technologies might also play a crucial role in the transition to the carbon-free energy future. In particular, there are the oxy-fuel combustion technologies that might help to reduce the proportion of unburned fuel and increase the efficiency of the power plant while reducing the emissions of flue gases. Our paper focuses on the role and the place of the near-zero emission technologies in the production of clean energy. We applied economic and mathematical models for assessing the prospects for applying oxy-fuel combustion technology in thermal power plants, taking into account the system of emission quotas and changes in the fuel cost. Our results demonstrate that at the current fuel prices, it is advisable to use economical combined cycle gas turbines (CCGT). At the same time, when quotas for greenhouse gas emissions are introduced and fuel costs increase by 1.3 times, it becomes economically feasible to use the oxy-fuel combustion technology which possesses significant economic advantages over CCGT with respect to the capture and storage of greenhouse gases.This article belongs to the Special Issue Innovation in Energy Security and Long-Term Energy Efficiency ⅡThis research was funded by the RF President Council on Grants, grant number MD- 914.2020.6