Vilnius Gediminas Technical University
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The Location Selection for Roundabout Construction Using Rough BWM-Rough WASPAS Approach Based on a New Rough Hamy Aggregator
No full textAn adequately functionally located traffic infrastructure is an important factor in the mobility of people because it affects the quality of traffic, safety and efficiency of carrying out transportation activities. Locating a roundabout on an urban network is an imperative for road engineering to address traffic problems such as reduction of traffic congestion, enhancement of security and sustainability, etc. Therefore, this paper evaluates potential locations for roundabout construction using Rough BWM (Best Worst Method) and Rough WASPAS (Weighted Aggregated Sum Product Assessment) models. Determination of relative criterion weights on the basis of which the potential locations were evaluated was carried out using the Rough BWM method. In this paper, in order to enable the most precise consensus for group decision-making, a Rough Hamy aggregator has been developed. The main advantage of the Hamy mean (HM) operator is that it can capture the interrelationships among multi-input arguments and can provide DMs more options. Until now, there is no research based on HM operator for aggregating imprecise and uncertain information. The obtained indicators are described through eight alternatives. The results show that the fifth and sixth alternatives are the locations that should have a priority in the construction of roundabouts from the perspective of sustainable development, which is confirmed throughout changes of parameter k and with comparing to other methods in the sensitivity analysis.This article belongs to the Special Issue Multi-Objective and Multi-Attribute Optimisation for Sustainable Development Decision Aidin
A Dynamic Fuzzy Approach Based on the EDAS Method for Multi-Criteria Subcontractor Evaluation
No full textSelection of appropriate subcontractors for outsourcing is very important for the success of construction projects. This can improve the overall quality of projects and promote the qualification and reputation of the main contractors. The evaluation of subcontractors can be made by some experts or decision-makers with respect to some criteria. If this process is done in different time periods, it can be defined as a dynamic multi-criteria group decision-making (MCGDM) problem. In this study, we propose a new fuzzy dynamic MCGDM approach based on the EDAS (Evaluation based on Distance from Average Solution) method for subcontractor evaluation. In the procedure of the proposed approach, the sets of alternatives, criteria and decision-makers can be changed at different time periods. Also, the proposed approach gives more weight to newer decision information for aggregating the overall performance of alternatives. A numerical example is used to illustrate the proposed approach and show the application of it in subcontractor evaluation. The results demonstrate that the proposed approach is efficient and useful in real-world decision-making problems.This article belongs to the Special Issue Multiple-Criteria Decision-Making (MCDM) Techniques for Business Processes Information Managemen
Investigation of the Rupture Surface of the Titanium Alloy Using Convolutional Neural Networks
No full textThe research of fractographic images of metals is an important method that allows obtaining valuable information about the physical and mechanical properties of a metallic specimen, determining the causes of its fracture, and developing models for optimizing its properties. One of the main lines of research in this case is studying the characteristics of the dimples of viscous detachment, which are formed on the metal surface in the process of its fracture. This paper proposes a method for detecting dimples of viscous detachment on a fractographic image, which is based on using a convolutional neural network. Compared to classical image processing algorithms, the use of the neural network significantly reduces the number of parameters to be adjusted manually. In addition, when being trained, the neural network can reveal a lot more characteristic features that affect the quality of recognition in a positive way. This makes the method more versatile and accurate. We investigated 17 models of convolutional neural networks with different structures and selected the optimal variant in terms of accuracy and speed. The proposed neural network classifies image pixels into two categories: “dimple” and “edge”. A transition from a probabilistic result at the output of the neural network to an unambiguously clear classification is proposed. The results obtained using the neural network were compared to the results obtained using a previously developed algorithm based on a set of filters. It has been found that the results are very similar (more than 90% similarity), but the neural network reveals the necessary features more accurately than the previous method
Risk Assessment in PPP Projects by Applying Different MCDM Methods and Comparative Results Analysis
No full textRecently, risk assessment has become one of the most challenging issues in the areas of construction and public-private partnerships (PPPs). To address risk assessment issues, various decision-making techniques have been proposed, each with its own specific disadvantages and advantages. This paper investigates step-wise weight assessment ratio analysis (SWARA), complex proportional assessment (COPRAS), fuzzy analytic network process (FANP), fuzzy analytic hierarchy process (FAHP), fuzzy technique for order of preference by similarity to ideal solution (FTOPSIS), simple additive weighting (SAW) and evaluation based on distance from average solution (EDAS) in order to define how various multi-attribute decision-making (MADM) methods compare when used for risk assessment in PPP projects. For this study, 5 risk assessment criteria and 10 types of risk used in Iranian highway PPP projects were selected. Four suitability and applicability tests were used to measure agreement between the rankings derived from the MADM methods. Final results show that all techniques had approximately the same rankings of risk assessment, with the SWARA, COPRAS, and EDAS methods performing slightly better. The findings of this study will help the parties in PPP and construction projects to select the best risk assessment method.This article belongs to the Special Issue Rational Decision Making in Risk Managemen
Guidelines on Designing Conceptual Framework for Strategic Management with Application to the Energy Industry
No full texthe role of strategic management is to handle the day-to-day needs of the firms with respect to current events of fluctuating markets so that they can effectively reach to their pre-planned, long-term goals. This study aims to explain the steps taken to design a new conceptual framework in the strategic management department of the National Iranian Gas Export Company (NIGEC), as well as the main components of the conceptual framework. It first goes through the logic behind the techniques applied to design this conceptual framework, and then each component is explained as to why it works as part of an integrated conceptual framework. This new framework is part of a change regime in the organisation along with the whole oil industry in Iran aimed at contributing to directing the organisations confronted with rapidly altering environments. The insights of this study shed light on the basics of designing an adjusted conceptual framework for managers and researchers, and all companies faced with constant internal and external challenges and other characteristics of modern organisations
Performance of Rayleigh-Based Distributed Optical Fiber Sensors Bonded to Reinforcing Bars in Bending
No full textDistributed Optical Fiber Sensors (DOFSs), thanks to their multiple sensing points, are ideal tools for the detection of deformations and cracking in reinforced concrete (RC) structures, crucial as a means to ensure the safety of infrastructures. Yet, beyond a certain point of most DOFS-monitored experimental tests, researchers have come across unrealistic readings of strain which prevent the extraction of further reliable data. The present paper outlines the results obtained through an experimental test aimed at inducing such anomalies to isolate and identify the physical cause of their origin. The understanding of such a phenomenon would enable DOFS to become a truly performant strain sensing technique. The test consists of gradually bending seven steel reinforcement bars with a bonded DOFS under different conditions such as different load types, bonding adhesives, bar sections and more. The results show the bonding adhesives having an influence on the DOFS performance but not on the rise of anomalies while the reasons triggering the latter are narrowed down from six to two, reaching a strain threshold and a change in structure’s deformative behavior. Further planned research will allow identification of the cause behind the rise of strain-reading anomalies.This article belongs to the Special Issue Bridge Structural Health Monitoring and Damage IdentificationFinancial support from the Research Council of Lithuania and the European Union Structural Fund
(Project no.: 09.3.3-LMT-K-712-01-0145) and financial support provided by the European Union Horizon 2020
research and innovation program under the Marie Sklodowska-Curie grant agreement No. 642453
A Novel Model for Determining Public Service Compensation in Integrated Public Transport Systems
No full textIn free market conditions, if public passenger transport services are commercially unprofitable, there will be no interest for transport companies to perform them. However, directly because of the citizens’ interests, on the one hand, and indirectly because of the economy, passenger public transport services have become of a general public interest. The authorities must prepare appropriate legal fair market conditions, based on which public transport will be subsidized and conducted. In order to achieve that, for the mutual benefit of the public, users and transport companies, it is necessary that the right Public Service Obligation Model (PSO model or in some literature PCS—Public Service Compensation) be defined. Within this study, the optimal approach to assigning a PSC contract to transport companies for performing the PSO in integrated and regular public passenger transport systems is determined. A novel model, presented in this paper, can help national, regional and local authorities to choose and determine the way and level of PSCs for conducting the public transport of passengers and establishing a sustainable public passenger transport system.This article belongs to the Section Sustainable TransportationThis research was funded by the Ministry of Education, Science and Technological Development of
the Republic of Serbia, under the Project TR36012: Research of technical-technological, staff and organizational
capacity of Serbian Railways, from the viewpoint of current and future European Union
Peculiarities of illegal immigrant’s intrusions into road freight transport units in the France - UK corridor
No full textThe World Economic Crisis has increased such processes as poverty, discrimination and war. As a consequence, many people from Africa, Middle East and Asia started to immigrate to Europe. There were over one million unauthorized immigrants entering Europe in 2015. However, not all countries want and can accept refugees. A long-time frame for assessing asylum applications or frequent rejections encourages refugees to migrate illegally by intruding freight transport units to cross the border of their chosen European country. The intrusion of illegal immigrants into road freight units to cross borders without being noticed has caused a great deal of damage to the international freight transportation companies. This article presents results of the study aimed at investigation of peculiarities of illegal immigrant’s intrusions into road freight transport units moving along the corridor France – United Kingdom
Assessment of the impact of the common agricultural policy direct payments system on agricultural sustainability
Get PDFDisertaciniame darbe nagrinėjamas tvarumo koncepcijos integravimas į Bendrosios žemės ūkio politikos (BŽŪP) labiausiai finansuojamą priemonę – tiesioginių išmokų (TI) sistemą, jos poveikis žemės ūkio tvarumui, vertinimo ypatybės, siejančios BŽŪP poveikio žemės ūkio sektoriui ir tvarumo vertinimo metodikas. Pagrindinis disertacijos tikslas – nustatyti tiesioginių išmokų sistemos poveikį žemės ūkio tvarumui. Šiam tikslui pasiekti buvo sukurtas TI sistemos poveikio žemės ūkio tvarumui vertinimo modelis, kurio galutinis rezultatas – integruotas indeksas.
Tyrimo metu sprendžiami tokie pagrindiniai uždaviniai: išanalizavus mokslinę literatūrą buvo siekiama ištirti tvarumo koncepcijos prigimtį ir pokyčius bei pritaikyti juos žemės ūkio raidai vertinti; nustatyti TI sistemos indėlį, siekiant žemės ūkio tvarumo, identifikuojant ryšius tarp žemės ūkio tvarumo dimensijų ir TI sistemos tikslų, reformuojant BŽŪP; išanalizuoti žemės ūkio politikos ir jos priemonių poveikio žemės ūkio tvarumui vertinimo instrumentus, siekiant pagrįsti TI sistemos poveikio žemės ūkio tvarumui vertinimo modelį; sukurti BŽŪP TI sistemos poveikio žemės ūkio tvarumui vertinimo modelį, patikrinti jo pritaikomumą analizuojant TI sistemos poveikį skirtingo dydžio ūkininkų ūkių tvarumui Lietuvoje 2004–2014 m. ir parengti išvadas, atsižvelgiant į gautus vertinimo rezultatus.
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.
Pirmajame skyriuje atskleista tvarumo koncepcijos raida ir jos integravimas į žemės ūkio politiką bei TI sistemą, nustatytos sąsajos tarp TI sistemos tikslų ir tvarumo dimensijų, reformuojant BŽŪP, aptarti BŽŪP poveikio tvarumo vertinimo įrankiai. Antrajame skyriuje pateikiamas TI sistemos poveikio žemės ūkio tvarumui vertinimo modelis, aprašomi jo elementai, rodiklių atranka kuriant indeksą, kaip galutinį modelio produktą. Pristatytas modelyje kombinuotas daugiakriterinių metodų SAW, TOPSIS ir EDAS taikymas. Trečiajame skyriuje pateikiamos apskaičiuoto indekso ir jį sudarančių subindeksų reikšmės Lietuvoje, nustatomos TI sistemos poveikio žemės ūkio tvarumui priežastys.
Disertacijos tema paskelbti 4 straipsniai, perskaityti pranešimai Lietuvos ir užsienio mokslinėse tarptautinėse konferencijose, stažuotės metu Fodžos universitete (Italijoje)
Morphology of CdSe-based coatings formed on polyamide substrate
No full textCadmium selenide (CdSe)-based layers were formed on the surface of polyamide 6 (PA) substrate film by treating PA film samples with potassium selenotrithionate (K2SeS2O6) solution (seleniumization) and then with cadmium (II) acetate, Cd(CH3COO)2, solution (cadmiumization). The morphology of CdSe- based layers was investigated by atomic force and scanning electron microscopies. It was determined that the formation of CdSe-based layers proceeds unevenly in the form of islands, which later tends to agglomerate. Therefore the surface of the layers formed is relatively uneven and rather rough. After seleniumization and cadmiumization procedures the average height of this layer have tendency to decrease from 337 after 1 h of seleniumization to 153 nm at 2.5 and 3.5 h of seleniumization. It was also determined that the RMS of formed layers slightly increases (from 32 to 42 nm) with the prolongation of PA seleniumization (from 1 to 2.5 hours) and it decreases (from 43 to 22 nm) with the increase of the temperature (from 50 °C to 70 °C) of seleniumized PA treatment by the solution containing Cd (II) salt. XPS data show that in coatings, substantial amounts of both cadmium hydroxide (Cd(OH)2) and cadmium oxide (CdO) are formed on the surface and within deeper layers of formed coatings. It was also determined that only a small fraction (∼0.1 % – 2 %) of cadmium selenide is present on the surface of formed coating after seleniumization and cadmiumization, while within in the deeper layers the concentrations of both Cd and Se were much higher and the fractions of Cd(OH)2 and CdO decreased