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Improved Quick Sort Average Performance Time by Combining with Selection and Insertion Algorithms
No full textIn many real-world applications, sorting is a crucial data structure. Sorting algorithms are methods for rearranging a collection of unsorted items into a desired format or order. A lot of sorting algorithms are developed to enhance the time performance, space complexity, and correctness. Selection, insertion, and quick sort are the most common kinds of sorting algorithms, each one has advantages and disadvantages. The advantages of selection sort algorithm are that it provides simplicity and efficiency for sorting small data, whereas the efficiency is bad for large data. On the other hand, the advantages of quick sort algorithm such that simplicity and efficiency for sorting small data, whereas its disadvantage is the overhead of recursive calling. To achieve the advantages of selection and insertion sorting algorithms, and overcome the drawback of quick sort, a merging of selection and quick sort, as well as a merging of insertion and quick sort, are proposed and analyzed and then compared to each other individually. This paper uses both theoretical and experimental data.Taip / Ye
Assessment of smart growth indicators progress in EU: cohesion approach
No full textSmart Growth, a concept present since the inception of the European Union, has grown in significance with each subsequent programming period. Eventually, it solidified as a pivotal strategy for Europe2020. Post-2020, it has evolved into the Smart Specialization Strategy (S3) for the period 2021–2027, and discussions now include the S4+ strategy, focusing on smart specialization strategies for sustainable and inclusive growth. This study aims to evaluate the cohesion level of smart growth indicators and their temporal development among EU member states, examining three key indicators: employment, tertiary education, and gross expenses on R&D (GERD) within the timeframe of 2010–2022. The findings reveal a consistent long-term trend of growth in the cohesion level of these indicators among EU member states, indicating a noteworthy convergence. Particularly in employment, the indicators demonstrate striking similarities across all countries, reflecting the highest level of cohesion within the EU. Conversely, in the case of GERD, the most substantial variations among EU countries are observed. These results underscore the success of Smart Growth initiatives in fostering convergence across EU member states, especially in terms of employment. However, challenges persist, particularly in achieving cohesion in research and development investments. Understanding these dynamics is crucial for shaping effective policies to sustain and enhance smart growth strategies in the ever-evolving European landscape.Taip / Yes
Biblioteka informuoja, 2024 Nr. 35 (679)
No full textNaujai į Web of Science ir Scopus įtrauktų Vilnius Gedimino technikos darbuotojų publikacijų sąrašai ir kitos bibliotekos aktualijos.35 (679)202
Carassius gibelio hematologinių ir biocheminių streso biožymenų bei fiziologinių rodiklių įvertinimas Kuršių marių pakrantės zonose
No full textThis study aimed to assess the health status of Carassius gibelio, a comparatively tolerant fish species, in the largest coastal lagoon in Europe – the Curonian Lagoon. Haematocrit and glucose levels were evaluated as reliable biomarkers of stress responses in fish. Additionally, non-specific physiological biomarkers, including hepatosomatic index and condition factor, were utilized to assess the environmental quality of the Curonian Lagoon. Fish samples were collected from two sites: the southern part of Klaipėda port, known as Kiaulės Nugara Island, and the central part of the Curonian Lagoon near Ventė Cape. Based on the multi-biomarker responses of C. gibelio, differences were observed between the two sampling sites, but not statistically significant. Consequently, C. gibelio cannot be recommended as a suitable bioindicator of environmental pollution and is not recommended for biomonitoring surveys of the Curonian Lagoon.Šiuo tyrimu siekta įvertinti Carassius gibelio, palyginti tolerantiškos taršai žuvų rūšies, sveikatos būklę didžiausioje Europos priekrantės lagūnoje – Kuršių mariose. Buvo vertinami hematologiniai (hematokrito kiekis), biocheminiai (gliukozės koncentracija), fiziologiniai (kepenų somatinis indeksas, įmitimo koeficientas) rodikliai kaip patikimi žuvų reakcijos į stresą biožymenys. Žuvys buvo gaudomos pietinėje marių pakrantėje ties Klaipėdos uostu, netoli Kiaulės nugaros salos, ir centrinėje Kuršių marių dalyje ties Ventės ragu. Vertinant biožymenų atsakus žuvyse reikšmingų skirtumų tarp tirtų stočių nenustatyta. Todėl nerekomenduojama C. gibelio rūšies naudoti kaip aplinkos taršos bioindikatoriaus.Taip / YesResearch Council of LithuaniaS-BIODIVERSA- 23-
Compensated Stepped Microstrip Lines: A Novel Approach for Impedance Discontinuity Mitigation
No full textModern electronic devices operate at frequencies where interconnects function as transmission lines, necessitating meticulous management of characteristic impedance (Z0) to avert signal degradation and power losses. This paper delves into the manipulation of microstrip characteristic impedance through variations in trace inductance and capacitance. It proposes a reference plane cut-out compensation technique to mitigate impedance inconsistencies introduced by component pads of varied sizes, which disrupt the uniformity of the microstrip. The technique involves adjusting capacitance by altering the distance to the reference plane. Experimental validation on a 6-layer printed circuit board (PCB) device confirms the effectiveness of the proposed method in maintaining impedance close to the target value of 50Ω, critical for high-frequency applications. Measurements using a vector network analyzer demonstrate substantial impedance improvement up to 35Ω through compensation, offering insights into practical impedance control strategies for high-frequency dense PCB designs.Joint Research Collaborative Seed Grant Program between National Taipei University of Technology and Vilnius Gediminas Technical UniversityTaip / YesNTUT-VGTU-113-01/2023-0
University-industry cooperation: a case study of student innovation projects in Latvia
No full textThe purpose of this study is to identify the most common forms of university-industry cooperation in Latvia, as well as to evaluate the motivating, facilitating, and barrier-creating factors of such cooperation. A case study approach was used to conduct the research, analyzing three projects of the ERDF program “Innovation Grants for Students”, analyzing their documentation, and conducting interviews with the companies involved in the projects as well as project management representatives. The study showed that university-industry cooperation in Latvia is at a stage of development where it is essential to build mutual trust and communication between universities and business.Taip / Yes
Hidrinto augalinio aliejaus ir biobutanolio mišiniais veikiančio dyzelinio variklio energinių ir emisijos rodiklių tyrimai
No full textThe transportation industry is transforming the “Resource-efficient Europe” initiative to promote economic progress, increase competitiveness, and deliver high-quality mobility promotion services. This initiative encourages using locally sourced renewable biofuels, such as biobutanol-based fuel, to reduce ecological impact and increase renewable energy sources in overall energy consumption. Researchers in Lithuania explore second-generation biodiesel mixtures and biobutanol for further integration in the Lithuanian transport sector.
The quest for sustainable and environmentally friendly fuel alternatives for internal combustion engines has led to exploring second-generation biofuels, such as Hydrotreated Vegetable Oil (HVO) and biobutanol mixtures. This research evaluates the energy and ecological impacts of substituting conventional diesel with these biofuels in a compression ignition engine.
The experimental setup involved a 1.9 TDI engine type 1Z, operating at a constant speed of 2000 rpm under varying loads and exhaust gas recirculation (EGR) rates. Fuels tested included conventional diesel (D100), HVO100, and mixtures of HVO with 5%, 10%, and 20% biobutanol in percentage proportions by volume (HVOB5, HVOB10, and HVOB20). Key parameters studied are brake thermal efficiency (BTE), smoke emissions, NOX, CO2 emissions, and particulate number (PN). Theoretical investigations further analysed the correlation between energy and ecological indicators across different fuel compositions.
The research showed that using HVO100 and its mixtures with biobutanol greatly reduced the amount of smoke and CO2 emissions compared to D100. The emissions went down even more as the biobutanol concentration increased in HVO. However, BTE showed a decrease with higher biobutanol concentration under constant load conditions. Specifically, HVOB20 demonstrated a reduction in BTE by approximately 1.4% compared to D100. NOX emissions were lowest with HVO100, indicating a reduction in NOX generation through increased EGR rates. Theoretical investigations underscored a strong correlation between ecological and energy parameters, highlighting the potential of biofuel mixtures to meet specified emission standards (Eur – Lex, 2019).
The usage of HVO and biobutanol in compression ignition engines presents a promising avenue for improving ecological indicators without significantly compromising energy efficiency. Nevertheless, the research identifies a need for further research into the long-term effects of these biofuels on engine reliability and performance. This research supports the transition towards alternative renewable fuels, reducing smoke emissions and CO2 levels, thereby contributing to the global effort to combat climate change.Transporto sektorius pertvarkomas pagal iniciatyvą „Tausiai išteklius naudojanti Europa“, kuria skatinama ekonominė pažanga, didinamas konkurencingumas ir plečiamos mobilumo paslaugos. Šia iniciatyva skatinama naudoti vietinės kilmės atsinaujinančius biodegalus, tokius kaip biobutanolio pagrindu pagamintus degalus, sumažinant transport priemonų poveikį aplinkai ir siekiant, kad kuo didesnę suvartojamos energijos dalį sudarytų iš atsinaujinančių šaltinių gaunama energija. Mokslininkai Lietuvoje tiria antros kartos biodyzelino mišinius ir biobutanolį, kad juos integruoti Lietuvos transporto sektoriuje.
Tvarių ir aplinką tausojančių vidaus degimo variklių alternatyviųjų degalų paieškos paskatino tyrinėti antros kartos biodegalus, tokius kaip hidrinti augaliniai aliejai (HVO) ir biobutanolio mišiniai. Šiame tyrime vertinamas įprasto dyzelino pakeitimo šiais biodegalais slėginio uždegimo variklyje energinis ir ekologinis poveikis.
Eksperimentuose naudotas 1,9 TDI 1Z tipo variklis, veikiantis pastoviu 2000 aps/min greičiu, esant įvairioms apkrovoms ir skirtingam išmetamųjų dujų recirkuliacijos (EGR) režimui. Tirti degalai buvo įprastinis dyzelinas (D100), HVO100 ir HVO mišiniai su 5 %, 10 % ir 20 % biobutanolio tūrio (HVOB5, HVOB10 ir HVOB20). Pagrindiniai ištirti parametrai yra: efektyvusis naudingumo koeficientas (BTE), dūmingumas, NOX, CO2 emisija ir kietųjų dalelių skaičius (PN). Atliekant teorinius tyrimus analizuotas ryšys tarp VDV ekologinių ir energinių rodiklių esant skirtingiems degalų mišiniams.
Tyrimas parodė, kad naudojant HVO100 ir jo mišinius su biobutanoliu dūmingumas ir CO2 emisija mažesni, nei naudojant D100. Išmetamųjų teršalų kiekis mažėja, didinant biobutanolio koncentraciją HVO degaluose. BTE sumažėja esant didesnei biobutanolio koncentracijai ir pastovioms variklio apkrovos sąlygoms. HVOB20 parodė, kad BTE sumažėjo maždaug 1,4 %, palyginti su D100. NOX emisija buvo mažiausia naudojant HVO100, tai rodo, kad padidinus EGR režimą susidaro mažiau azoto oksidų. Teorinių tyrimų rezultatai atskleidė stiprią ekologinių ir energinių parametrų koreliaciją ir parodė, kad biodegalų mišiniai turi didelį potencialą ir gali atitikti keliamus emisijos standartus (Eur – Lex, 2019).
HVO ir biobutanolio mišinių panaudojimas slėginio uždegimo vidaus degimo variklyje yra perspektyvus būdas pagerinti ekologinius rodiklius nesumažinant energinio efektyvumo. Tyrimo metu nustatyta, kad būtina toliau tirti ilgalaikį šių biodegalų poveikį variklio veikimo patikimumui. Šiuo tyrimu pagrindžiamas perėjimas prie atsinaujinančių alternatyviųjų degalų naudojimo, mažinant dūmingumą ir CO2 išmetimą, taip prisidedant prie pasaulinių pastangų kovoti su klimato kaita.Taip / Ye
Comparative review on integration levels between design and analysis systems /
No full textBuilding design is a broad and intensive collaborative process that involves a multitude of tasks and responsibilities that need to be accomplished in a timely and qualitative manner. The design process has a clearly expressed iterative nature - each solution is initially raised as a hypothesis, which is further discussed, analysed, calculated, checked, including compliance with normative requirements, and then final decisions are made after analysing several possible alternatives. This takes place in each team (discipline) of the project participants by comparing analysis results and anticipating the possible impact of decisions on the solutions and results of other design teams (disciplines). Therefore, it is very important to coordinate, synchronize, reconcile, and manage these decision making iterations in a collaborative environment. The Building Information Modelling (BIM) technology encourages the development of harmonized information production and management processes, creating preconditions for real collaboration between design partners in a unified model (the prototype of real building) environment and enables this model to be used for multivariate virtual testing. This feature is realized through the integration of modelling and analysis and computing systems, when the data transfer from one system to another system ensures the connection between the physical and the analysis model and the integrity of their data. The article deals with the integration levels and systemic directions of architectural and structural modelling and design computation programs. The problem of physical construction model creation and conversion into analysis model is defined and the stages of Computer-Aided Design/Competer-Aidet Engineering (CAD/CAE) integrated design process are discussed
A Roadmap on Developing a Taxonomy for Text Data Mining
No full textOver the past decade, unstructured text data have increased significantly. Text data are utilized in various scientific research, such as sentiment analysis, semantic analysis, context extraction, or named-entity recognition. Nowadays, widely used Large Language Models (LLMs) are also based on text data. Depending on the type of task, different algorithms can be used to analyze the text data, such as classification, clustering, or the latest transformer models. In this paper, a systematic literature review of text data mining has been performed. During the research, the analysis of scientific articles was performed based on two different scientific databases: Web of Science and Google Scholar. The main aim of the research was to summarize the results of scientific researches, tasks, and methods used in text data analysis. The types of datasets and the language of the texts used in the research were also analyzed. Furthermore, the results obtained from the systematic literature that was performed allowed us to build a taxonomy of text data mining that can be helpful to other researchers.Taip / Ye
Biblioteka informuoja, 2024 Nr. 34 (678)
No full textNaujai į Web of Science ir Scopus įtrauktų Vilnius Gedimino technikos darbuotojų publikacijų sąrašai ir kitos bibliotekos aktualijos.34 (678)202