Vilnius Gediminas Technical University
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Multiple Criteria Evaluation of the EU Country Sustainable Construction Industry Lifecycles
No full textThis article looks at the trends and success of the sustainable construction industries in the EU member states, the UK and Norway. The research, covering the past three decades, revealed that different quality of life, macroeconomic, human development, construction and well-being factors define the sustainable construction industries in the EU member states, the UK and Norway. A multiple criteria decision matrix was created and analysed to look at the EU member countries, the UK and Norway from the perspective of their macro level environment and construction industries. Assessments of the sustainable construction industries were completed by using the COmplex PRoportional Assessment (COPRAS) and Degree of Project Utility and Investment Value Assessments (INVAR), two analysis methods. A look was taken at the dependencies linking the indicators related to the construction industries and macro level in the EU member countries, the UK and Norway. Then, the multiple criteria analysis of the construction industry’s utility degree and performances were completed, and recommendations were generated. A country’s perceived image and success can influence the economic behaviour of consumers. By and large, advanced and successful countries rarely become associated with a negative national image and their products and services rarely suffer negative consequences due to such association. This research, then, offers findings that can assist potential buyers in more rational decision-making when choosing of products and services based on a country of origin.This article belongs to the Special Issue Probabilistic and Fuzzy Approaches for Estimating the Life Cycle Costs of BuildingsThis project received funding from European Regional Development Fund (project No
01.2.2-LMT-K-718-01-0073) under grant agreement with the Research Council of Lithuania (LMTLT). The sponsor
had no involvement in the study design, the collection, analysis and interpretation of data, or the preparation of
the article
Extracellular-Ca2+-Induced Decrease in Small Molecule Electrotransfer Efficiency: Comparison between Microsecond and Nanosecond Electric Pulses
No full textElectroporation—a transient electric-field-induced increase in cell membrane permeability—can be used to facilitate the delivery of anticancer drugs for antitumour electrochemotherapy. In recent years, Ca2+ electroporation has emerged as an alternative modality to electrochemotherapy. The antitumor effect of calcium electroporation is achieved as a result of the introduction of supraphysiological calcium doses. However, calcium is also known to play a key role in membrane resealing, potentially altering the pore dynamics and molecular delivery during electroporation. To elucidate the role of calcium for the electrotransfer of small charged molecule into cell we have performed experiments using nano- and micro-second electric pulses. The results demonstrate that extracellular calcium ions inhibit the electrotransfer of small charged molecules. Experiments revealed that this effect is related to an increased rate of membrane resealing. We also employed mathematical modelling methods in order to explain the differences between the CaCl2 effects after the application of nano- and micro-second duration electric pulses. Simulation showed that these differences occur due to the changes in transmembrane voltage generation in response to the increase in specific conductivity when CaCl2 concentration is increased.This article belongs to the Section Drug Delivery and Controlled ReleaseThis research is funded by the European Social Fund according to the activity ‘Improvement of
researchers’ qualification by implementing world-class R&D projects’ of Measure No. 09.3.3-LMT-K-712-01-0188
Experimental Investigation of Linear Encoder’s Subdivisional Errors under Different Scanning Speeds
No full textOptical encoders are widely used in applications requiring precise displacement measurement and fluent motion control. To reach high positioning accuracy and repeatability, and to create a more stable speed-control loop, essential attention must be directed to the subdivisional error (SDE) of the used encoder. This error influences the interpolation process and restricts the ability to achieve a high resolution. The SDE could be caused by various factors, such as the particular design of the reading head and the optical scanning principle, quality of the measuring scale, any kind of relative orientation changes between the optical components caused by mechanical vibrations or deformations, or scanning speed. If the distorted analog signals are not corrected before interpolation, it is very important to know the limitations of the used encoder. The methodology described in this paper could be used to determine the magnitude of an SDE and its trend. This method is based on a constant-speed test and does not require high-accuracy reference. The performed experimental investigation of the standard optical linear encoder SDE under different scanning speeds revealed the linear relationship between the tested encoder’s traversing velocity and the error value. A more detailed investigation of the obtained results was done on the basis of fast Fourier transformation (FFT) to understand the physical nature of the SDE, and to consider how to improve the performance of the encoder.This article belongs to the Special Issue IWPMA (International Workshop on Piezoelectric Materials and Applications in Actuators) 201
Sustainable Cloud Service Provider Development by a Z-Number-Based DNMA Method with Gini-Coefficient-Based Weight Determination
No full textThe sustainable development of cloud service providers (CSPs) is a significant multiple criteria decision making (MCDM) problem, involving the intrinsic relations among multiple alternatives, (quantitative and qualitative) decision criteria and decision-experts for the selection of trustworthy CSPs. Most existing MCDM methods for CSP selection incorporated only one normalization technique in benefit and cost criteria, which would mislead the decision results and limit the applications of these methods. In addition, these methods did not consider the reliability of information given by decision-makers. Given these research gaps, this study introduces a Z-number-based double normalization-based multiple aggregation (DNMA) method to tackle quantitative and qualitative criteria in forms of benefit, cost, and target types for sustainable CSP development. We extend the original DNMA method to the Z-number environment to handle the uncertain and unreliability information of decision-makers. To make trade-offs between normalized criteria values, we develop a Gini-coefficient based weighting method to replace the mean-square-based weighting method used in the original DNMA method to enhance the applicability and isotonicity of the DNMA method. A case study is conducted to demonstrate the effectiveness of the proposed method. Furthermore, comparative analysis and sensitivity analysis are implemented to test the stability and applicability of the proposed method.This article belongs to the Special Issue Multiple Criteria Decision Making for Sustainable DevelopmentThe work was supported by the Scientific and Technological Research Program of Chongqing Municipal Education Commission under Grant No. KJ1500630, Chongqing Engineering Laboratory for Detection, Control and Integrated System, Chongqing Technology and Business University under Grant No.1456026, Scientific Research Foundation of Chongqing Technology and Business University under Grant No.2015–56–01
Risk identification and prioritization in banking projects of payment service provider companies: an empirical study
No full textIdentifying risks and prioritizing is important for payment service provider (PSP) companies to get banking projects and gain more market share. However, studies regarding the identification of risks and causal relationships are insufficient in the Iranian PSP industry and the industry is unique because of its characteristics. In this study, 30 experts involved with PSP companies are employed as the research sample. Eleven key risks and Forty-six sub-risks are also identified. Subsequently, the fuzzy decision-making trial and evaluation laboratory technique is applied to determine the effective and affected risks and the severity of their effects on each other. Finally, all risks are ranked. Due to the internal interrelationships of the main risks, the weight of each risk is calculated via the fuzzy analytic network process. As the second-level risks have no significant interrelationships, they are ranked via the fuzzy analytical hierarchy process. Moreover, the best-worst method is used to ensure that the obtained rankings are reliable. This study identifies the risks affecting the loss of banking projects and determines the impacts of these risks on each. A sensitivity analysis is then conducted on the weights of the criteria, and the results are compared.This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/
Assessment of the Segmentation of RGB Remote Sensing Images: A Subjective Approach
Full text linkThe evaluation of remote sensing imagery segmentation results plays an important role in the further image analysis and decision-making. The search for the optimal segmentation method for a particular data set and the suitability of segmentation results for the use in satellite image classification are examples where the proper image segmentation quality assessment can affect the quality of the final result. There is no extensive research related to the assessment of the segmentation effectiveness of the images. The designed objective quality assessment metrics that can be used to assess the quality of the obtained segmentation results usually take into account the subjective features of the human visual system (HVS). A novel approach is used in the article to estimate the effectiveness of satellite image segmentation by relating and determining the correlation between subjective and objective segmentation quality metrics. Pearson’s and Spearman’s correlation was used for satellite images after applying a k-means++ clustering algorithm based on colour information. Simultaneously, the dataset of the satellite images with ground truth (GT) based on the “DeepGlobe Land Cover Classification Challenge” dataset was constructed for testing three classes of quality metrics for satellite image segmentation.This article belongs to the Special Issue The Quality of Remote Sensing Optical Images from Acquisition to UsersThis research has received funding from the Research Council of Lithuania (LMTLT), agreement
No. S-MIP-19-27
Dynamic Expert System-Based Geographically Adapted Malware Risk Evaluation Method
Full text linkFast development of information systems and technologies while providing new opportunities for people and organizations also make them more vulnerable at the same time. Information security risk assessment helps to identify weak points and preparing mitigation actions. The analysis of expert systems has shown that rule-based expert systems are universal, and because of that can be considered as a proper solution for the task of risk assessment automation. But to assess information security risks quickly and accurately, it is necessary to process a large amount of data about newly discovered vulnerabilities or threats, to reflect regional and industry specific information, making the traditional approach of knowledge base formation for expert system problematic. This work presents a novel method for an automated expert systems knowledge base formation based on the integration of data on regional malware distribution from Cyberthreat real-time map providing current information on newly discovered threats. In our work we collect the necessary information from the web sites in an automated way, that can be later used in a relevant risk calculation. This paper presents method implementation, which includes not only knowledge base formation but also the development of the prototype of an expert system. It was created using the JESS expert system shell. Information security risk evaluation was performed according to OWASP risk assessment methodology, taking into account the location of the organization and prevalent malware in that area.This is an open access article distributed under the terms and conditions of the Creative Commons
Attribution-NonCommercial 4.0 International License
Aukšto dažnio stačiakampių impulsų elektroporacijos sistemos kūrimas ir tyrimas
No full textThe dissertation provides the research and development of the high-frequency square wave pulse electroporation system and proposes a topolgy of planar electroporation electrodes for real-time electroporation applications. An analysis and applied research of the electrical pulse forming circuits, the electric field generation technologies and the compensation circuits for high-frequency transient as well as the electric field distribution of planar electroporation electrodes are carried out.
The introductory chapter deals with the problem of the thesis, research goals and newness, describes the research methodology and defended statements.
The first chapter presents the most relevant scientific literature related to the main subjects of this dissertation. The electroporation phenomena and the dependence of the cell response on electrical pulses duration and frequency are presented. The review of submicrosecond and nanosecond electric pulse generators and high-frequency transient process compensation circuits are also presented. This Chapter concludes in formulating tasks the dissertation.
The second chapter presents simulation models of the high-voltage, high-frequency submicrosecond pulsed electric field (nsPEF) generator and planar electrodes for real-time electroporation. The SPICE model of pulse forming circuit is developed and the effects of the parasitic circuit elements and transient processes to the generated electric pulse are investigated. The chapter includes the potential applications and needs of the planar electrodes for electroporation. The topology of planar electrodes and its influence on electric field homogeneity are analysed using finite element method (FEM) in COMSOL Multiphysics environment.
The third chapter presents the research and development of novel high-frequency square-wave electroporation system. The developed system can produce single and bursts deliver adjustable square-wave electric pulses with load independent pulse fall time. The pulse amplitude, repetition frequency and pulse duration can be adjusted accordingly up to 3 kV, from 1 Hz to 3.5 MHz and from 100 ns to 1 ms. In this chapter, the system simulation and the experimental results are compared. The prototype system is successfully tested for the inactivation of the human pathogen Candida albicans.
The main results of the thesis were published in 6 scientific articles: three – in scientific journals included in Clarivate Analytics Web of Science database with impact factor, two – in international conference publications which are referred by Clarivate Analytics Web of Science database Proceedings, one article is printed in peer-reviewed scientific journal listed in Index Copernicus database. The research results were presented in 10 scientific conferences.Doctoral dissertatio
The Mechanical Properties of Centrifuged Concrete in Reinforced Concrete Structures
No full textThis article explores the influence of transverse reinforcement (spiral) and high-strength longitudinal reinforcements on the physical-mechanical properties of centrifuged annular cross-section elements of concrete. The test results of almost 200 reinforced, and over 100 control elements are summarizing in this article. The longitudinal reinforcement ratio of samples produced in the laboratory and factory varied from 1.0% to 6.0%; the transverse reinforcement ratio varied from 0.25% to 1.25%; the pitch of spirals varied from 100 mm to 40 mm and the concrete strength varied from 25 MPa to 60 MPa. Experimental relationships of coefficients for concrete strength, moduli of elasticity and limits of the longitudinal strain of centrifuged concrete in reinforced concrete structures in short-term concentrically compression were proposed.This article belongs to the Section Civil Engineerin
Knowledge Management Practice in General Education Schools as a Tool for Sustainable Development
No full textThe already scarce and further dwindling natural resources, increasing environmental pollution, and other environmental, economic, and social challenges that transcend national boundaries necessitate the continuous pursuit of the more responsible implementation of the principles of sustainable development in the public and business sectors, especially in general education schools, as the future and welfare of the society depend on education results. Therefore, the implementation of knowledge management practices in general education schools is one of the efficient ways of achieving the principles of sustainable development and their positive outcomes for society and the state. This research aimed to evaluate the peculiarities of applying knowledge management practices in general education schools for sustainable development. Research methods such as analysis of scientific literature, multiple-criteria assessment, survey, and expert evaluation were used to achieve the goal of the study. The results of the study showed that there is a high potential in general education schools for the application of knowledge management practices to achieve sustainable development. However, general education schools still face a lack of teachers’ motivation and a lack of financial resources to apply knowledge management practices and improve knowledge infrastructure for sustainability.This article belongs to the Special Issue Knowledge Management and Human Resources Management for Organizational SustainabilityThis research was funded by the European Union’s Horizon 2020 project H2020-MSCA-RISE-2014
CLUSDEVMED, Grant Agreement Number 645730730