Vilnius Gediminas Technical University
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Research on the Combustion, Energy and Emission Parameters of Various Concentration Blends of Hydrotreated Vegetable Oil Biofuel and Diesel Fuel in a Compression-Ignition Engine
No full textThis article presents our research results on the physical-chemical and direct injection diesel engine performance parameters when fueled by pure diesel fuel and retail hydrotreated vegetable oil (HVO). This fuel is called NexBTL by NESTE, and this renewable fuel blends with a diesel fuel known as Pro Diesel. A wide range of pure diesel fuel and NexBTL100 blends have been tested and analyzed: pure diesel fuel, pure NexBTL, NexBTL10, NexBTL20, NexBTL30, NexBTL40, NexBTL50, NexBTL70 and NexBTL85. The energy, pollution and in-cylinder parameters were analyzed under medium engine speed (n = 2000 and n = 2500 rpm) and brake torque load regimes (30–120 Nm). AVL BOOST software was used to analyze the heat release characteristics. The analysis of brake specific fuel consumption showed controversial results due to the lower density of NexBTL. The mass fuel consumption decreased by up to 4%, and the volumetric consumption increased by up to approximately 6%. At the same time, the brake thermal efficiency mainly increased by approximately 0.5–1.4%. CO, CO2, NOx, HC and SM were analyzed, and the change in CO was negligible when increasing NexBTL in the fuel blend. Higher SM reduction was achieved while increasing the percentage of NexBTL in the blends.This article belongs to the Special Issue Biofuels for Internal Combustion EngineThe Higher Education Excellence Program of the Ministry of Human Capacities in the biotechnology
research area of the Budapest University of Technology and Economics (BME FIKP-BIO)
A Risk Based Approach to Evaluating the Impacts of Zayanderood Drought on Sustainable Development Indicators of Riverside Urban in Isfahan-Iran
No full textIn recent years, the Zayanderood River in Isfahan-Iran has been encountered by hydrological imbalance and drought. Literature review shows that long-term climate change, drought, and disruption of the river’s water supply has led to depletion of underground aquifers and, consequently, gradual subsidence of the river and serious damage to old buildings and structures along the riverbank. This fact would be followed up by adverse environmental, social, and economic effect that could threaten the sustainable development of urban space. Therefore, it is necessary to use efficient risk identification and assessment approaches toward a more effective risk management. The goal of this study is to identify and prioritize the risks of river drought with regards to all three sustainable development areas including environmental, social, and economic. The research methodology was a mixed field method that included a set of questionnaires and interviews. To evaluate collected data, the analytic network process (ANP) method was used. Eighteen important risks were identified. Based on the results, decrease in the groundwater level, climate change, and gradual soil degradation were ranked first, second, and third, respectively. As this study examined the impacts of river drought on all three areas of sustainable development simultaneously and comprehensively, it is expected that the results will fill the existing theoretical and practical gap affecting improvements in assessment and management of sustainable development risks.This article belongs to the Special Issue Sustainability and Risks in Construction Managemen
Application of Histogram-Based Outlier Scores to Detect Computer Network Anomalies
No full textMisuse activity in computer networks constantly creates new challenges and difficulties to ensure data confidentiality, integrity, and availability. The capability to identify and quickly stop the attacks is essential, as the undetected and successful attack may cause losses of critical resources. The anomaly-based intrusion detection system (IDS) is a valuable security tool that is capable of detecting new, previously unseen attacks. Anomaly-based IDS sends an alarm when it detects an event that deviates from the behavior characterized as normal. This paper analyses the use of the histogram-based outlier score (HBOS) to detect anomalies in the computer network. Experimental results of different histogram creation methods and the influence of the number of bins on the performance of anomaly detection are presented. Experiments were conducted using an NSL-KDD dataset.This article belongs to the Special Issue State-of-the-Art of Cyber Securit
IT2 Hybrid Decision-Making Approach to Performance Measurement of Internationalized Firms in the Baltic States
No full textInternational activities of firms contribute to environmental socio-economic development and have a positive influence on prosperity of countries. The novelty of this study is to extend prevailing theory on the performance measurement of internationalized firms by suggesting a hybrid decision-making model based on interval type 2 fuzzy sets for the Baltic states. The integrated method is defined as the interval type-2 (IT2) decision making trial and evaluation laboratory qualitative flexible multiple criteria method (DEMATEL-QUALIFLEX). IT2 DEMATEL is used for weighting each criterion of internationalized firms and IT2 QUALIFLEX is applied for ranking the Baltic states, respectively. Within this context, six different criteria are defined for ranking the internationalized firms of the Baltic states. The ranking of all three countries enable us to conclude that Estonia demonstrates the best results of internationalized firms. Meanwhile, Latvia has the worst performance of internationalized firms. The findings are useful for decision makers responsible for supportive policies focused on the research and development (R&D) and internationalization of firms. The implications for managers lie in the awareness of necessary conditions for successful internationalization. The study extends prevailing knowledge on the performance measurement of internationalized firms and provides findings on multinational companies (MNCs) in the Baltic states’ context.This article belongs to the Section Economic and Business Aspects of Sustainabilit
A Multisensory, Green, and Energy Efficient Housing Neuromarketing Method
No full textGreen products, clean energy, energy union, green buildings, eco-innovations, environment-related, and similar initiatives and policies have become very popular and widely applied all over the world. A pleasant built environment (parks, flowerbeds, beautiful buildings) and a repulsive environment (noise, polluted surroundings) influence a buyer’s outlook on an advertisement differently. An aesthetic, comfortable, and clean built environment evokes positive emotional states, not only at the time of housing selection and purchase but during the building’s life cycle as well. Potential housing buyers always feel comfortable in certain built environments, and they are inclined to spend more time there. The issues needing answers are how to measure the segmentation/physiological indicators (crowd composition by gender and age groups), as well as the emotional (happy, sad, angry, valence) and physiological (heart rate) states of potential homebuyers realistically, to produce an integrated evaluation of such data and offer buyers rational, green, and energy efficient housing alternatives. To achieve this purpose, the Multisensory, green and energy efficient housing neuromarketing method was developed to generate the necessary conditions. Here, around 200 million multisensory data recordings (emotional and physiological states) were accumulated, and the environmental air pollution (CO, NO2, PM10, volatile organic compounds) and noise pollution were investigated. Specific green and energy efficient building case studies appear in this article to demonstrate the developed method clearly. The obtained research results are in line with those from previous and current studies, which state that the interrelation of environmental responsiveness and age forms an inverse U and that an interest in green and energy efficient housing depends on age.This article belongs to the Section Energy and EnvironmentThis project has 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)
Eliciting Weights of Significance of Criteria for a Monitoring Model of Performance of SMEs for Successful Insolvency Administrator’s Intervention
No full textSmall and medium-sized enterprises (SMEs) are accounted for as a major part of the economy of the EU in terms of part of the population employed, turnover, value-added, etc. Causes of insolvency of SMEs can be different; they are categorized in the paper. A considerable shift from resolving cases of bankruptcy with the sole aim to satisfy creditors’ rights to augmenting and enhancing liquidation and reorganization procedures evolved interest of the authors in creating efficient bankruptcy prediction models and, in particular, methodologies for evaluation and monitoring of the performance of SMEs. In the paper, we reviewed several initiatives and instruments created by the EU for supporting SMEs. The paper laid a foundation for creating a more comprehensive methodology for evaluation of the state of a firm undergoing the process of reorganization. A hierarchy structure of criteria for the evaluation of SMEs was used in the paper; methodologies for eliciting weights of importance of criteria from experts and gauging the level of concordance of opinions of experts were applied. Resulting weights of criteria of performance of an insolvent SME were obtained; the importance of the managerial category of criteria was revealed. Prominent features of hierarchy structures and methodology of using the structure for calculating ultimate weights were described and demonstrated. Gauging concordance of opinions of experts revealed a satisfactory level of concordance of opinions of experts; this allowed to prepare the ultimate weights of criteria for multiple criteria evaluation of SMEs for further research
Internal Combustion Engine Analysis of Energy Ecological Parameters by Neutrosophic MULTIMOORA and SWARA Methods
No full textThe investigation for new innovative solutions to reduce transport pollution is a priority for the European Union (EU). This study includes energy and a sustainable environment, as well as transport, logistics, and information and communication technologies. Energy ecological parameters of internal combustion depend on many factors: fuel, the fuel injection time, engine torque, etc. The engine’s energy ecological parameters were studied by changing engine torques, using different fuels, and changing the start of the fuel injection time. The selection of the optimum parameters is a complex problem. Multicriteria decision-making methods (MCDM) present powerful and flexible techniques for the solution of many sustainability problems. The article presents a new way of tackling transport pollution. The analysis of the energy ecological parameters of the experimental internal combustion engine is performed using the neutrosophic multi-objective optimization by a ratio analysis plus the full multiplicative form (MULTIMOORA) and step-wise weight assessment ratio analysis (SWARA) methods. The application of MCDM methods provides us with the opportunity to establish the best alternatives which reflect the best energy ecological parameters of the internal combustion engine.This article belongs to the Special Issue Sustainable Energy Development Strategies: Energy Efficiency and Renewable
Antitumor Response and Immunomodulatory Effects of Sub-Microsecond Irreversible Electroporation and Its Combination with Calcium Electroporation
No full textIn this work, we have investigated the feasibility of sub-microsecond range irreversible electroporation (IRE) with and without calcium electroporation in vivo. As a model, BALB/C mice were used and bioluminescent SP2/0 myeloma tumor models were developed. Tumors were treated with two separate pulsed electric field (PEF) pulsing protocols PEF1: 12 kV/cm × 200 ns × 500 (0.006 J/pulse) and PEF2: 12 kV/cm × 500 ns × 500 (0.015 J/pulse), which were delivered with and without Ca2+ (168 mM) using parallel plate electrodes at a repetition frequency of 100 Hz. Both PEF1 and PEF2 treatments reduced tumor growth and prolonged the life span of the mice, however, the PEF2 protocol was more efficient. The delay in tumor renewal was the biggest when a combination of IRE with calcium electroporation was used, however, we did not obtain significant differences in the final mouse survival compared to PEF2 alone. Anti-tumor immune responses were also investigated after treatment with PEF2 and PEF2+Ca. In both cases the treated mice had enlarged spleens and increased spleen T cell numbers, lower percentages of suppressor cell subsets (conventional CD4+CD25+ Treg, CD4+CD25−DX5+ Tr1, CD8+DX5+, CD4+CD28−, CD8+CD28−), changed proportions of Tcm and Tef/Tem T cells in the spleen and increased amount of tumor cell specific antibodies in the sera. The treatment based on IRE was effective against primary tumors, destroyed the tumor microenvironment and induced an anti-tumor immune response, however, it was not sufficient for complete control of tumor metastasis.This article belongs to the Special Issue Electric Field Based Therapies in Cancer Treatment: a Selection of Studies Presented at the 3rd World Congress on ElectroporationThis research was funded by Research Council of Lithuania, grant number S-MIP-19-22
Interaction between remuneration, employment and productivity
Get PDFDisertacijoje vertinamas ryšys tarp darbo apmokėjimo, užimtumo ir produk-tyvumo bei teorinės ir praktinės produktyvumo vertinimo prielaidos. Tyri-mo objektas yra ES šalių produktyvumas ir efektyvus jį lemiančių veiksnių valdymas, siekiant aukštesnio šalies konkurencingumo. Disertacijos tikslas – nustačius produktyvumui įtakos turinčius veiksnius, sukurti metodiką (koncepciją), kuri leistų kryptingai paskirstyti finansinius išteklius tarp pro-duktyvumą veikiančių veiksnių siekiant aukštesnio konkurencingumo. Dar-be sprendžiami pagrindiniai uždaviniai: analizuojami darbo apmokėjimo, užimtumo teoriniai aspektai; analizuojamas produktyvumas, jį lemiantys veiksniai bei jų įtaka konkurencingumui; ES šalių klasteriui formuojama finansinių išteklių paskirstymo metodika ir apibrėžiama produktyvumo įta-ka šalies konkurencingumui.
Disertaciją sudaro įvadas, trys skyriai, bendrosios išvados, literatūros sąrašas, autorės publikacijų disertacijos tema sąrašas.
Įvade aptariama suformuluota darbo problema, apibrėžiamas darbo ak-tualumas, tyrimų objektas, pristatomas darbo tikslas ir uždaviniai, aptariama tyrimų metodika, atskleistas darbo mokslinis naujumas, pagrindžiama darbo praktinė reikšmė, įvardyti ginamieji teiginiai. Įvado pabaigoje pagrindžiamas darbo praktinis aprobavimas ir pristatomos autorės publikacijos disertacijos tema.
Pirmasis skyrius skirtas literatūros apžvalgai. Atskleidžiamos teorinės darbo apmokėjimo, užimtumo ir produktyvumo koncepcijos, darbo užmo-kesčio nustatymo teorijos, užimtumo formos ir įvertinama technologinės plėtros ir žmogiškųjų išteklių reikšmė konkurencingumui. Nagrinėjama dar-bo apmokėjimo, užimtumo ir produktyvumo sąveika bei įtaka konkuren-cingumui. Skyriaus pabaigoje formuluojamos išvados ir tikslinami uždavi-niai.
Antrame skyriuje pateikta produktyvumo vertinimo metodika bei pa-aiškinama, kaip pasaulio konkurencingumo indekso ir visuminio produkty-vumo veiksnio svarba bei Dikio-Fulerio bei Grangerio priklausomybės skaičiavimų rezultatai yra adekvataus portfelio metodikos pagrindas.
Trečiame skyriuje atliktas ES šalių klasterizavimas pagal darbo užmo-kesčio, bendrojo vidaus produkto ir kapitalo (gamybos priemonių) dydį, užimtumo lygį bei investicijų (į žinių įgijimą ir kompetencijas) kryptį. Taip pat atskleisti priežastiniai ryšiai tarp darbo užmokesčio, užimtumo, gamybos priemonių, žinių/kompetencijų ir produktyvumo bei suformuota finansinių išteklių paskirstymo metodika.
Disertacijos tema paskelbta 17 straipsnių: 8 straipsniai paskelbti recen-zuojamuose mokslo žurnaluose, 9 – recenzuojamoje nacionalinės ir tarptau-tinės konferencijos medžiagoje. Disertacijos tema perskaityta 17 pranešimų konferencijose (4 jaunųjų mokslininkų konferencijoje, 2 nacionalinėje kon-ferencijoje ir 11 tarptautinėse mokslo konferencijose).Disertacij
The assessment of sustainable development of a country’s regions
Get PDFDisertacijoje nagrinėjama šalies regionų darnios plėtros vertinimo problema. Mokslinės literatūros analizė atskleidė, kad iki šiol nepavyko rasti metodi-kos, kuri leistų įvertinti regiono plėtrą ir kiekybiniu, ir kokybiniu aspektu. Visos metodikos, skirtos esamos regionų plėtros būklės nustatymui, vertina tik kiekybinę plėtros pusę, neatsižvelgiant į kokybinę jos pusę.
Disertacijos tyrimo objektas – regionų plėtra. Disertacijos tikslas – kie-kybiškai įvertinti šalies regionų tvariai darnią plėtrą siekiant efektyvaus jų plėtros valdymo. Buvo suformuluoti šie pagrindiniai uždaviniai: atlikti šalies regionų darnios plėtros vertinimui skirtos mokslinės literatūros ana-lizę; sudaryti regionų tvariai darnios plėtros kiekybinio vertinimo metodiką; patikrinti pasiūlytą metodiką Lietuvos regionų pavyzdžiu.
Disertaciją sudaro įvadas, trys skyriai, bendrosios išvados, naudotos li-teratūros ir autorės publikacijų disertacijos tema sąrašai bei aštuoni priedai.
Įvade aptariama tiriamojo darbo problema, atskleidžiamas darbo aktua-lumas, pateikiamas tyrimų objektas, formuluojamas darbo tikslas bei užda-viniai, aprašoma tyrimų metodika, išryškinamas darbo mokslinis naujumas ir darbo rezultatų praktinė reikšmė, pateikiami ginamieji teiginiai. Įvado pa-baigoje pristatomos autorės publikacijos disertacijos tema ir pranešimai konferencijose bei disertacijos struktūra.
Pirmasis skyrius skirtas darnios plėtros aktualumo ir jos vertinimo klau-simų analizei. Aprašyta regioninės politikos svarba šalies regionų plėtrai, pateikta tvariai darnios plėtros koncepcijos samprata bei darnios plėtros ver-tinimo analizė. Skyriaus pabaigoje formuluojamos išvados ir tikslinami di-sertacijos uždaviniai. Antrasis darbo skyrius skirtas šalies regionų tvariai darnios plėtros vertinimo metodologijai. Pateikiama siūloma šalies regionų tvariai darnios plėtros vertinimo metodika, išsamiai aprašomi etapai ir veiksmų seka. Sudaryta metodika skirta nustatyti pasiektą šalies regionų tvariai darnios plėtros lygį. Trečiajame skyriuje yra praktiškai pritaikoma darbe siūloma šalies regionų tvariai darnios plėtros vertinimo metodika. Su-kurtos metodikos praktinis pritaikomumas patikrinamas atliekant empirinį tyrimą Lietuvos regionų pavyzdžiu.
Disertacijos tema paskelbti 6 straipsniai: du – mokslo žurnaluose, įt-rauktuose į Clarivate Analytics duomenų bazės leidinius, turinčius citavimo rodiklį, vienas – mokslo žurnale, Clarivate Analytics duomenų bazės leidi-nyje, neturinčiame citavimo rodiklio, vienas – kitų tarptautinių duomenų bazių leidininyje, du – recenzuojamose tarptautinių konferencijų medžiago-se. Disertacijos tema perskaityti 4 pranešimai mokslinėse konferencijose.Disertacij