VGTU Journals (Vilnius Gediminas Technical University - Vilnius Tech)
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Structural parameters and comparative analysis of the performance of four beetle elytron plate walls
No full textThis article presents the characteristics of four straw-filled beetle elytron plate (BEPsc) nonload-bearing walls, with their thermal and mechanical properties ascertained by the finite element method, focusing on structural parameters reported in previous studies and further optimized in this paper. The results are as follows: 1) The sequence of the four models’ mechanical and thermal insulation properties with the reported structural parameters is given. The mechanical properties are mainly affected by the core layer’s out-of-plane bending moment of inertia Ix. The insulation capability is mainly governed by the minimum cross section of the core concrete. Based on this result, a BEP with nonuniform cross-sectional honeycomb walls is proposed. 2) Further optimization is conducted on the two models with the weakest mechanical and thermal properties. The I-beam beetle elytron plate (IBEPsc) is proven most suitable for nonload-bearing walls. The potential for end-trabecular beetle elytron plate (EBEPsc) in hollow floors is expected. 3) As biomimetic models emerge constantly, it is of great significance to conduct parallel comparisons between new and old models to determine their performance levels and advantages. This paper provides an example for selecting suitable BEPs for applications and an inspiration for more work on screening outstanding biomimetic models
Technological innovation cooperative behavior analysis for mega construction projects based on TPB
No full textDue to the complex nature of mega construction projects (MCPs), technological innovation risks have significantly increased. Cooperation is widely accepted as a proactive approach to resolving these risks. An in-depth study of technological innovation cooperative behavior (TICB) helps understand the underlying reasons, but studies need to pay more attention to it. This study explored the factors affecting TICB for MCPs and developed a conceptual model based on the Theory of planned behavior (TPB). It established a structural equation model to verify the relationship between influencing factors. An example verified the feasibility of the model. The results show that cooperative attitude, subjective cooperative norm, perceived cooperative behavior control, and cooperative scenarios positively affect cooperative behavior through cooperative intention. Cooperative attitude plays a mediating role between cooperative scenarios and cooperative intention. Perceived cooperative behavior control has no direct effect on cooperative behavior. This study provides a theoretical reference to guide future empirical studies and enriches the knowledge of TICB for MCPs
A review of multi-criteria decision-making methods for building assessment, selection, and retrofit
No full textMultiple criteria decision-making (MCDM) has experienced significant growth in recent years, owing to its capacity to integrate even contradictory criteria. This study conducted a comprehensive literature review of MCDM for assessing, selecting, and retrofitting buildings. The bibliometric search used a search algorithm in specialized databases. A filtering and expansion process was done by reviewing references, and 91 relevant articles were selected. The analysis revealed that in a group of studies, socioeconomic criteria were used to assess the vulnerability of buildings. On the other hand, some research integrated the three dimensions of sustainability (economic, social, and environmental) along with safety considerations when identifying optimal retrofit alternatives. Classic MCDMs are prevalent in research within this field. Among the most used methods, the Analytic Hierarchy Process (AHP) was employed for criteria weighting, Simple Additive Weighting (SAW) for constructing vulnerability indices, and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) for building retrofitting. This literature review contributes to the path toward a holistic renovation of the existing building stock, providing recommendations for future research to improve decision-making solutions for integrating the safety and sustainability of existing buildings
BIM and orthogonal test methods to optimize the energy consumption of green buildings
No full textThe construction industry’s rapid growth significantly impacts energy consumption and environmental health. It is crucial to develop optimization strategies to enhance green building energy efficiency and encompass comprehensive analysis methods. This study aims to introduce and validate a novel framework for optimizing energy efficiency design in green buildings by integrating Building Information Modeling (BIM) technology, Life Cycle Cost (LCC) analysis, and orthogonal testing methods, focusing on enhancing energy efficiency and reducing life cycle costs. The optimization parameters for the building envelope are identified by analyzing energy consumption components and key green building factors. The orthogonal testing method was applied to streamline design options. Building Energy Consumption Simulation (BECS) software and LCC analysis tools were employed to calculate each optimized option’s total annual energy consumption and the current life cycle costs. Using the efficiency coefficient method, each optimization scheme’s energy consumption and economic indicators were thoroughly analyzed. The framework’s validity and applicability were confirmed through an empirical analysis of a campus green building case in Fujian Province, demonstrating that the optimized framework could reduce energy consumption by 4.85 kWh/m2 per year and lower costs by 38.89 Yuan/m2 compared to the reference building. The case study highlights the framework’s significant benefits in enhancing environmental performance and economic gains. The results provide critical parameter selection and offer scientific and technological support for the design of building energy efficiency, promoting optimization techniques and sustainable development within the construction industry
Measurement of electrical conductivity and resistivity of Cu-Nb18% microcomposite conductor and its welded joint
No full textSystems generating strong magnetic fields are widely used in modern fundamental and applied research as well as in the most innovative industrial processes. These devices generate magnetic fields that reach 5–100 T and the conductors are subjected to a huge Lorentz force, so the conductor material must be extremely strong (UTS ≥ 700 MPa) and have a good specific electrical conductivity (IACS ≥ 60%). Since traditional conductors such as copper, aluminum, gold, and silver cannot withstand such loads, microcomposite materials have been developed that are characterized by such high strength and good specific electrical conductivity. This paper reviews the specific electrical conductivity and specific electrical resistance characteristics of conductor and factors affecting them, methods of measuring these electrical characteristics as well as properties of Cu-Nb18% microcomposite conductor. This paper also describes the methodology for measuring the specific electrical conductivity and specific electrical resistance of the Cu-Nb18% microcomposite conductor solid and with welded joint (welded by using butt welding). The comparison of application possibilities of used methodologies and obtained characteristics was carried out.
Article in Lithuanian.
Cu-Nb 18 % mikrokompozitinio laidininko ir jo virintinių jungčių elektrinio laidumo ir savitosios elektrinės varžos matavimo ypatumai
Santrauka
Šiuolaikiniuose fundamentiniuose, taikomuosiuose tyrimuose bei inovatyviausiuose industriniuose procesuose yra plačiai taikomi stiprių magnetinių laukų sistemos. Šie įrenginiai generuoja magnetinius laukus, kurie siekia 5–100 T, o laidininkai yra veikiami didžiulės Lorentzo jėgos, todėl laidininkų medžiaga turi būti itin tvirta (UTS ≥ 700 MPa) ir turėti gerą savitąjį elektrinį laidumą (IACS ≥ 60 %). Kadangi tradiciniai laidininkai tokie kaip varis, aliuminis, auksas, sidabras negali atlaikyti tokių apkrovų, buvo sukurtos mikrokompozitinės medžiagos, kurios pasižymi dideliu stipriu ir turi gerą savitąjį elektrinį laidumą. Šiame darbe apžvelgiamos laidininkų savitojo elektrinio laidumo bei savitosios elektrinės varžos charakteristikos, jiems įtaką darantys veiksniai, šių elektrinių charakteristikų matavimo metodikos, Cu-Nb 18 % mikrokompozitinio laidininko savybės. Taip pat šiame darbe yra aprašomos Cu-Nb 18 % mikrokompozitinio laidininko su virintine jungtimi (pagaminta taikant sandūrinį kontaktinį suvirinimą) ir vientiso Cu-Nb 18 % laidininko savitojo elektrinio laidumo ir savitosios elektrinės varžos matavimo metodikos, atliktas metodikų taikymo galimybių ir gautų charakteristikų palyginimas.
Reikšminiai žodžiai: elektrinis laidumas, savitoji elektrinė varža, Cu-Nb mikrokompozitiniai laidininkai, virintinės jungtys, matavimai
Investigation of low-cost piezoelectric force sensor
No full textThe use of piezoelectric force sensors is well-established in industrial systems and devices, but their adoption in consumer products has been limited due to the high cost of implementation as well as complex peripheral electronics. This paper proposes an alternative approach to force sensing using commonly available piezoelectric buzzer elements, which could potentially reduce the cost of such sensors and promote their integration into consumer products. The paper represents experimental investigations of output characteristics of two different piezoelectric force sensors, which are based on disc-shaped buzzers. The goal of the investigation is to indicate and experimentally confirm electromechanical characteristics of proposed piezoelectric sensors under different sensing and signal management conditions. The results of the investigations showed that piezo buzzers have the potential to serve as cost-effective force sensors in consumer products as well as in different mechatronic systems.
Article in English.
Pjezoelektrinių jėgos sensorių tyrimas
Santrauka
Pjezoeletriniai jėgos sensoriai jau seniai yra naudojami industrinėse sistemose ir prietaisuose. Bet šių jutiklių pritaikymas buitinėje technikoje bei kituose plataus vartojimo prietaisuose iki šiol buvo ribotas dėl didelių diegimo kaštų ir sudėtingos periferinės elektronikos, reikalingos pjezoelektrinių jėgos sensorių signalams interpretuoti. Šiame straipsnyje bus nagrinėjamas alternatyvus, plačiai paplitusių pjezogarsiakalbių (angl. piezo buzzer) panaudojimas jėgos matavimams atlikti. Straipsnyje pateikiami eksperimentiniai dviejų skirtingų pjezoelektrinių jėgos jutiklių, pagrįstų disko formos garsiakalbiais, charakteristikų tyrimai. Tyrimo tikslas – parodyti ir eksperimentiškai patvirtinti siūlomų pjezoelektrinių jutiklių elektromechanines charakteristikas skirtingomis matavimo ir signalo valdymo sąlygomis. Tyrimų rezultatai parodė, kad pjezogarsiakalbiai gali būti ekonomiški jėgos jutikliai tiek plataus vartojimo gaminiuose, tiek įvairiose mechatroninėse sistemose.
Reikšminiai žodžiai: jėgos jutiklis, jėgos matavimas, pjezoelektrinės medžiagos, disko formos pjezoelektriniai garsiakalbiai
Assessing the impact of AI integration on advancing circular practices in construction
No full textThis study provides a thorough examination of the potential and problems associated with integrating artificial intelligence (AI) into the circular economy (CE) framework within Sri Lanka’s construction industry. The study uses approach that combines primary data obtained through a questionnaire survey involving several stakeholders with secondary data analysis from academic sources. The data were interpreted using descriptive and statistical analysis, such as Kendall’s Tau correlation and Pearson’s correlation. There is an optimistic view about AI’s potential advantages, including resource and energy conservation, even if the technology is still in its early integration phases. Nevertheless, there are still significant barriers to adoption, such as a lack of knowledge and reluctance to change. The study offers a conceptual framework for combining AI with CE principles, including IoT, computer vision, and machine learning technologies to enhance the Reduce, Reuse, and Recycle (3R) CE principles. This framework supports cooperative efforts, skill development, and policy development to support sustainable building practices in Sri Lanka.
Article in English.
Dirbtinio intelekto, taikant žiedinę ekonomiką statyboje, poveikio vertinimas
Santrauka
Šiame tyrime nagrinėjamos dirbtinio intelekto (DI) integravimo į žiedinės ekonomikos (ŽE) sistemą Šri Lankos statybos pramonėje galimybės ir ribojantys veiksniai. Tyrime taikomas metodas, kuriame derinami duomenys, gauti atlikus kelių suinteresuotųjų šalių anketinę apklausą, ir duomenys, gauti atlikus mokslo literatūros šaltinių analizę. Duomenys buvo interpretuojami taikant aprašomąją ir statistinę analizes, Kendall’s Tau koreliaciją ir Pearson’o koreliaciją. Optimistiškai vertinant, nors DI technologija dar tik pradedama integruoti statybų sektoriuje, pastebimi jos privalumai, pvz., išteklių ir energijos taupymas. Nepaisant to, vis dar esama didelių diegimo kliūčių, tokių kaip žinių trūkumas ir nenoras keistis. Tyrime siūloma koncepcinė sistema, sistema, kurioje DI derinamas su ŽE principais, įskaitant daiktų internetą, kompiuterinę regą ir mašininio mokymosi technologijas. Tai leistų patobulinti ŽE principus: „mažinti, pakartotinai naudoti ir perdirbti“ (3R). Taikant siūlomą sistemą skatinamas bendradarbiavimas, įgūdžių ugdymas ir politikos formavimas siekiant remti tvarią statybos praktiką Šri Lankoje.
Reikšminiai žodžiai: dirbtinis intelektas, užstatyta aplinka, žiedinė ekonomika, tvarumas, Šri Lanka
The factor of war as a threat to sustainable development and a challenge for corporate social responsibility
No full textThe purpose of the study is to analyze the practice of involving multinational companies in achieving the Sustainable Development Goals (SDGs), in general, and the response to SDG 16 “Peace, Justice and Strong Institutions”. The research methodology involves a comparative analysis of the attitude towards the SDG leaders of sustainable development and MNCs that currently continue to work on the Russian market is presented. The conducted research showed that MNCs mostly recognize their impact on achieving SDG 16, but at the same time (1) they put it at a medium or low priority level; (2) emphasize justice and strong institutions. As a result of the study, it was proven that the existing approach to assessing the level of achievement of SDG 16 does not take into account modern conditions of warfare and needs to be revised. The novelty of the study lies in the further development of scientific approaches to assessment of international business contribution to SDGs achievement and promotion of sustainable peace, opposition to military aggression, as well as substantiating the need to change approaches (criteria) to assessing the achievement of SDG 16
Assessing the factors impacting shipping container dwell time: a multi-port optimization study
No full textOcean transportation is the most preferred mode of transportation that represents a significant role in the global trade. Ocean transportation comprises around 80% of the aggregate worldwide cargo volume. This research paper focused on evaluating the factors that influence the dwell time of the shipping containers. Dwell time is one of the important port performance parameters which evaluates the time spent by the container in a port. In this research, the data from the fourteen major ports was collected and analysed across the variables, such as cycle, size, mode, status, delivery and tracking technology for evaluating the variation in container dwell time. OLS regression method (Ordinary least squares) along with independent sample T test was adopted for the analysis of 2.8 million container data entries utilizing python for big data analysis and SPSS. For the top three ports with lowest RMSE (Root mean square error), Port A – 15.6 %, Port G – 15.7 % and Port L – 15.86 %, a qualitative study was performed to identify the reasons for the variation in dwell time. The major reasons identified included free days period, trans-shipment port, high rail frequency, industrial hubs in the vicinity of the ports for lower dwell time. A qualitative research framework was presented as the research outcomes and reasons for variations in a multiport study
Determinants of ERM quality and its impact on company value
No full textCompany value results from how well a company has managed its resources to achieve business benefits. However, there are always risks associated with conducting business, and effective risk management (ERM) can help reduce those risks so that they stay in the way of the entity’s performance goals. This study examines the factors that affect ERM quality, such as company size, auditor caliber, concentrated ownership, and director oversight, and how this affect business success. Purposive sampling produced a sample of 552-panel data used in this study’s research of manufacturing firms in Indonesia and Malaysia. With the aid of STATA software, this study discovered a favorable relationship between auditor quality and ERM and also impact firm size, auditor quality, concentrated ownership, and ERM on company value. The expansion test revealed that while the quality of auditors in Malaysian companies had a positive effect on firm value while those in Indonesia did not, and vice versa, the quality of auditors in Indonesian companies had a stronger positive effect on ERM quality than the quality of auditors in Malaysian companies. In contrast to businesses in Malaysia, monitoring of directors has a beneficial impact on a company’s worth in Indonesia