Vilnius Gediminas Technical University
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The recalculation of the weights of criteria in MCDM methods using the bayes approach
Get PDFThe application of multiple criteria decision-making methods (MCDM) is aimed at choosing
the best alternative out of the number of available versions in the absence of the apparently dominant
alternative. One of the two major components of multiple criteria decision-making methods is
represented by the weights of the criteria describing the considered process. The weights of the
criteria quantitatively express their significance and influence on the evaluation result. The criterion
weights can be subjective, i.e., based on the estimates assigned by the experts, and the so-called
objective, i.e., those which assess the structure of the data array at the time of evaluation. Several
groups of experts, representing the opinions of various interested parties may take part in the
evaluation of criteria. The evaluation data on the criterion weights also depend on the mathematical
methods used for calculations and the estimation scales. In determining the objective weights, several
methods, assessing various properties or characteristics of the data array’s structure, are usually
employed. Therefore, the use of the procedures, improving the accuracy of the evaluation of the
weights’ values and the integration of the obtained data into a single value, is often required. The
present paper offers a new approach to more accurate evaluation of the criteria weights obtained
by using various methods based on the idea of the Bayes hypothesis. The performed investigation
shows that the suggested method is symmetrical and does not depend on the fact whether a priori
or posterior values of the weights are recalculated. This result is the theoretical basis for practical
use of the method of combining the weights obtained by various approaches as the geometric
mean of various estimates. The ideas suggested by the authors have been repeatedly used in the
investigation for combining the objective weights, for recalculating the criteria weights after obtaining
the estimates of other groups of experts and for combining the subjective and the objective weights.
The recalculated values of the weights of the criteria are used in the work for evaluating the quality
of the distant courses taught to the students
Interaction between landscape architecture and urbanism
Get PDFŠiuolaikiniame moksle ir praktikoje kraštovaizdžio architektūros kompetencijų sričiai priskiriami vis sudėtingesni miesto tvarkymo, atnaujinimo ir vystymo uždaviniai. Miestas yra daugiafunkcinis organizmas, todėl planuotojai, urbanistikos bei kraštovaizdžio mokslininkai ieško būdų, kaip kartu spręsti iškylančius tarpdisciplininius klausimus, kurių centre, be abejo, yra žmonių gerovės poreikiai. Disertacijoje nagrinėjama kraštovaizdžio architektūros ir urbanistikos sąveikos tema. Tyrimu ieškoma atsakymų, kaip kraštovaizdžio architektūra gali būti naudinga siekiant tvaraus gamtos ir miesto sambūvio, kas sudaro kraštovaizdžio architektūros kūrybos lauką miesto aplinkoje bei, kas lemia kraštovaizdžio architektūros priemonių raišką urbanistiniame kraštovaizdyje. Tyrimo tikslas – atskleidžiant kraštovaizdžio architektūros raidą ir vaidmenį mieste, sukurti tvaraus vystymosi principais paremtą kraštovaizdžio architektūros ir urbanistikos sprendinių sąveikos optimizavimo metodinį modelį.
Disertaciją sudaro įvadas, trys skyriai, bendrosios išvados, naudotos literatūros sąrašas, priedai. Įvade pristatoma disertacijoje nagrinėjama problema, jos aktualumas, tyrimo objektas, darbo metodai, naujumas, ginamieji teiginiai ir darbo struktūra. Pirmajame skyriuje aptariama kraštovaizdžio architektūros sampratos evoliucija, kraštovaizdžio architektūros profesinės veiklos laukas, kraštovaizdžio architektūros raiška XIX–XXI amžių urbanistiniuose procesuose. Analizuojami ir apibendrinami kraštovaizdžio ir urbanistikos sąsajų mokslinių tyrimų aspektai bei miesto aplinkos tyrimų metodai. Antrajame skyriuje kuriami kraštovaizdžio architektūros ir urbanistikos sąveikos tyrimo metmenys. Tiriami šešių Lietuvos miestų bendrųjų planų sprendiniai gamtinio karkaso ir želdynų sistemos vystymo ir kraštovaizdžio architektūros aspektu, analizuojama Lietuvos ir užsienio ekspertų nuomonė dėl kraštovaizdžio architektūros vaidmens miesto kūrime. Sudaromas kraštovaizdžio architektūros ir urbanistikos sprendinių sąveikos tyrimo modelis: nustatomi pagrindiniai optimalios sąveikos principai, sudaroma tvarumo ir ekologinės etikos principais grįsta trinarė tyrimo kriterijų sistema. Trečiajame skyriuje pristatomas kraštovaizdžio architektūros ir urbanistikos sprendinių sąveikos optimizavimo metodinis modelis, kuriame sąveikos tyrimo rezultatai interpretuojami ir konceptualizuojami taikant kraštovaizdžio architektūros metodus. Aptariamos sąveikos optimizavimo metodinio modelio mokslinio ir praktinio pritaikymo ekonominės, teisinės ir tvaraus miesto planavimo sąlygos.
Disertacijos tema paskelbti penki straipsniai recenzuojamuose mokslo žurnaluose ir trys kituose recenzuojamuose leidiniuose. Be to, disertacijos tema perskaityti šeši pranešimai ir pristatytas vienas stendinis pranešimas Lietuvos bei kitų šalių mokslinėse konferencijose
Correlation between Fructan Exohydrolase Activity and the Quality of Helianthus tuberosus L. Tubers
Get PDFJerusalem artichoke tubers have diverse applications in the food industry as well as in biotechnology. Their suitability depends mostly on the inulin content. Seasonal fluctuations of fructan exohydrolase activity responsible for inulin degradation was investigated in the tubers of three Jerusalem artichoke cultivars. The changes of fructan exohydrolase activity positively correlated with the changes of the content of total and short fructooligosaccharides. Therefore, to extract inulin with higher degree of polymerization for biotechnological purposes, the tubers of Jerusalem artichoke should be uprooted in autumn before the level of fructan exohydrolase reaches its maximum. If short fructooligosaccharides are desirable, the tubers in late autumn or spring tubers overwintered in soil are suitable
A New Methodology for Improving Service Quality Measurement: Delphi-FUCOM-SERVQUAL Model
No full textThe daily requirements and needs imposed on the executors of logistics services imply the need for a higher level of quality. In this, the proper execution of all sustainability processes and activities plays an important role. In this paper, a new methodology for improving the measurement of the quality of the service consisting of three phases has been developed. The first phase is the application of the Delphi method to determine the quality dimension ranking. After that, in the second phase, using the FUCOM (full consistency method), we determined the weight coefficients of the quality dimensions. The third phase represents determining the level of quality using the SERVQUAL (service quality) model, or the difference between the established gaps. The new methodology considers the assessment of the quality dimensions of a large number of participants (customers), on the one hand, and experts’ assessments on the other hand. The methodology was verified through the research carried out in an express post company. After processing and analyzing the collected data, the Cronbach alpha coefficient for each dimension of the SERVQUAL model for determining the reliability of the response was calculated. To determine the validity of the results and the developed methodology, an extensive statistical analysis (ANOVA, Duncan, Signum, and chi square tests) was carried out. The integration of certain methods and models into the new methodology has demonstrated greater objectivity and more precise results in determining the level of quality of sustainability processes and activities.This article belongs to the Special Issue Multi-Criteria Decision-Making Techniques for Improvement Sustainability Engineering Processe
Impact of the Uridine–Cytidine Kinase Like-1 Protein and IL28B rs12979860 and rs8099917 SNPs on the Development of Hepatocellular Carcinoma in Cirrhotic Chronic Hepatitis C Patients—A Pilot Study
Get PDFBackground and objectives: The hepatitis C virus (HCV) is the major causative agent of hepatocellular carcinoma (HCC) in the western world. The efficacy of surveillance programs for early detection of HCC is not satisfactory: many tumors are diagnosed at the late, incurable stages. Therefore, there is a need in reliable prognostic markers for the proper follow-up of HCV-positive patients. The aim of the present study was to assess the prognostic value of the uridine–cytidine kinase-like protein 1 (UCKL-1), a putative oncoprotein, together with genetically determined polymorphisms in the interleukin 28B (IL28B) gene (rs12979860, rs8099917) in the development of HCC in HCV-positive cirrhotic patients. Materials and Methods: We included 32 HCV cirrhotic patients, 21 (65.6%) of whom had HCC. The expression of UCKL-1 was assessed in liver tissue sections, using immunohistochemistry. For IL28B rs12979860 and rs8099917 genotype analysis, the corresponding genomic regions were amplified by polymerase chain reaction (PCR) with appropriate primers. Results: We have found that UCKL-1 expression was significantly increased in HCC (p = 0.003). The presence of rs8099917 TT single-nucleotide polymorphism (SNP) elevated the chances of HCC manifestation more than sevenfold (OR = 7.3, p = 0.0273). The presence of rs12979860 CC SNP also heightened HCC chances more than sevenfold (OR = 7.5, p = 0.0765). Moreover, in the HCC group, a combination of IL28B rs12979860 non-TT and rs8099917 TT genotypes was observed more often, compared with the non-HCC group. Other combinations of IL28B rs12979860 and rs8099917 SNIPs were associated with a reduced risk of HCC development, approximately at the same extent. Conclusions: The presence of IL28B rs8099917 TT and rs12979860 CC SNPs, but not the intensity of UCKL-1 expression, is strongly associated with increased chances of HCC development in HCV-positive cirrhotic patients.This research was funded by Research Council of Lithuania, grant number TAP LU-1/2016
An Overview of Multi-Criteria Decision-Making Methods in Dealing with Sustainable Energy Development Issues
No full textThe measurement of sustainability is actively used today as one of the main preventative instruments in order to reduce the decline of the environment. Sustainable decision-making in solving energy issues can be supported and contradictory effects can be evaluated by scientific achievements of multi-criteria decision-making (MCDM) techniques. The main goal of this paper is to overview the application of decision-making methods in dealing with sustainable energy development issues. In this study, 105 published papers from the Web of Science Core Collection (WSCC) database are selected and reviewed, from 2004 to 2017, related to energy sustainability issues and MCDM methods. All the selected papers were categorized into 9 fields by the application area and into 10 fields by the used method. After the categorization of the scientific articles and detailed analysis, SWOT analysis of MCDM approaches in dealing with sustainable energy development issues is provided. The widespread application and use of MCDM methods confirm that MCDM methods can help decision-makers in solving energy sustainability problems and are highly popular and used in practice.This article belongs to the Special Issue Sustainable Energy Development Strategies: Energy Efficiency and RenewablesThe European Social Fund funded this research under the No. 09.3.3-LMT-K-712 “Development of Competences of Scientists, other Researchers and Students through Practical Research Activities” measure
Review of Surface Plasmon Polaritons in Nanostructured Metamaterials
No full textHerein, we discover the new kinds of surface wave on nanostructured metamaterial (MM),
crossing the light line with a substantial portion at lower frequencies lying above the free space light line. Interestingly, the propagation of such surface waves is found to be sensitive to the parameters of the materials employed in nanostructures. Furthermore, the Ferrel-Berreman modes are observed under the certain conditions, opening a gateway towards device fabrications.This is an open-access article distributed under the terms of the Creative
Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium,
provided the original author and source are credited
Shrinkage-free tension stiffening law for various concrete grades
No full textThe present study proposes a new tension stiffening law for reinforced concrete (RC) that takes into account the shrinkage effect occurring prior to the external loading. Due to the restraining action of reinforcement, shrinkage induces tension stresses in the concrete which may significantly reduce the crack resistance and increase deformations of the RC member. The proposed tension stiffening model is based on the test data of seven experimental programs reported in the literature, including 108 RC tension members covering a wide range of concrete grade, reinforcement ratio and bar diameter. The study has shown that shrinkage drastically changes the shape of tension stiffening relations with reinforcement ratio being the most important parameter responsible for this effect. This study reports a limited validation analysis of the proposed constitutive law based on experimental data reported herein. For that tests on four tensile RC members with measured free shrinkage strain have been carried out. The comparative analysis has shown good agreement between the experimental and predicted load–strain and tension stiffening relations.The authors gratefully acknowledge the financial support provided by the Research Council of Lithuania (project No. 09.3.3-
LMT-K-712-01-0145)
Evaluating the Impacts of Integrated Pollution on Water Quality of the Trans-Boundary Neris (Viliya) River
No full textThe trans-boundary area between the Europe Union and other countries is highly susceptible to changes in water quality and variations in the potential pollution load that could influence its eco-systems significantly. The Neris (Viliya) River is one of the biggest surface water bodies in Lithuania and Belarus with an ecologically important area protected by international legislation. The study was aimed at evaluating the impacts of integrated pollution on water quality of the Neris River taking into account different storm-water flows and ecological scenarios. For this purpose, qualitative and quantitative statistical evaluation was set up and calculation was done; different integrated pollution loads of the catchment area were estimated. The evaluation considered a decrease in river discharge due to changes in the regional storm-water flow and technological development that should lead to the growing covered surface and a reduction in the untreated storm-water flows. The obtained results indicated that, in the case of storm-water treatment, the total nitrate and phosphate concentrations will decrease, while in the cases of changes in combined suspended solid, the concentration of nutrients will decrease. Thus, a trans-boundary storm-water treatment plant of the Viliya River is required as it should eliminate pollution accumulation and restore its acceptable environmental status. A coordinated international project for the entire catchment of the Neris (Viliya) River based on the specifications and requirements of the EU Water Framework Directive (EU 2000) should be developed and implemented. Subsequently, ecological river-use policies should be established at the international level, which should offer considerable perspectives for the sustainable development of the area.This article belongs to the Section Environmental Sustainability and Application
Measuring Country Sustainability Performance Using Ensembles of Neuro-Fuzzy Technique
No full textGlobal warming is one of the most important challenges nowadays. Sustainability practices and technologies have been proven to significantly reduce the amount of energy consumed and incur economic savings. Sustainability assessment tools and methods have been developed to support decision makers in evaluating the developments in sustainable technology. Several sustainability assessment tools and methods have been developed by fuzzy logic and neural network machine learning techniques. However, a combination of neural network and fuzzy logic, neuro-fuzzy, and the ensemble learning of this technique has been rarely explored when developing sustainability assessment methods. In addition, most of the methods developed in the literature solely rely on fuzzy logic. The main shortcoming of solely using the fuzzy logic rule-based technique is that it cannot automatically learn from the data. This problem of fuzzy logic has been solved by the use of neural networks in many real-world problems. The combination of these two techniques will take the advantages of both to precisely predict the output of a system. In addition, combining the outputs of several predictors can result in an improved accuracy in complex systems. This study accordingly aims to propose an accurate method for measuring countries’ sustainability performance using a set of real-world data of the sustainability indicators. The adaptive neuro-fuzzy inference system (ANFIS) technique was used for discovering the fuzzy rules from data from 128 countries, and ensemble learning was used for measuring the countries’ sustainability performance. The proposed method aims to provide the country rankings in term of sustainability. The results of this research show that the method has potential to be effectively implemented as a decision-making tool for measuring countries’ sustainability performanceThis article belongs to the Collection Advanced Methodologies for Sustainability Assessment: Theory and Practic