Journals Published by Vilnius Tech
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Investigating the influence of urban green spaces on urban heat island mitigation – taking four districts in Shijiazhuang as an example
Get PDFThe primary objective of this scholarly investigation is to elucidate the intricate interplay between the urban heat island (UHI) effect and municipal green spaces. The geographical focus includes the four areas with the highest urbanization rate in Shijiazhuang, China. To conduct this survey, ECOSTRESS remote sensing imagery was acquired during distinct temporal intervals–morning, midday, and evening. The data were collected using the equal-scale city blocks performed by the OpenStreetMap urban network and ECOSTRESS remote sensing images at different times (morning, noon and evening). Surface temperature inversion of satellite images was performed using ArcGIS 10.7 software to obtain surface temperature. The overarching aim was to discern the nuanced impact of urban parks on the surface temperatures of their proximate environs during the summer season. The findings of this investigation revealed that, in order to effectively ameliorate the discernible heat island effect (SUH), rejuvenation initiatives ought to be directed toward sites maintaining a distance from green spaces within the range of 160 to 370 meters. Furthermore, augmentation of green space configurations is recommended in vicinities characterized by building densities falling within the range of 0.2 to 0.3. Notably, in locales marked by high building density, park layouts should adhere to a more regularized design during the renovation process. Additionally, it is advisable to ensure that the spatial separation between distinct urban parks exceeds 900 meters. These empirical insights are poised to enhance the comprehension of urban planners regarding the intricate dynamics through which urban parks exert influence on municipal surface temperatures. Furthermore, the discerned patterns furnish pragmatic guidance for mitigating the heat island effect, thereby offering invaluable recommendations for urban planning endeavors
Prediction of the anti-carbonation performance of concrete based on random forest – least squares support vector machine model
Get PDFConcrete carbonation is a critical factor influencing the durability and longevity of concrete structures, particularly in urban environments. Traditional methods for predicting the anti-carbonation performance (ACP) of concrete often lack precision and fail to account for complex interactions between influencing factors. In this study, a novel hybrid model combining random forest (RF) regression with a least squares support vector machine (LSSVM) is proposed to enhance the accuracy of ACP predictions. The RF regression is utilized for feature selection, identifying the most significant factors affecting ACP and optimizing the input features for the LSSVM model. Our hybrid model is validated against a comprehensive dataset, demonstrating superior performance in predicting concrete carbonation resistance compared to conventional methods. Quantitative results show that the RF-LSSVM model achieves a root mean square error (RMSE) of 5e–5 and a high coefficient of determination (R-squared) of 0.999, indicating robust predictive capability and accuracy. The main novelty of this work lies in the integration of RF and LSSVM to create a robust, accurate, and practical tool for assessing the durability of concrete structures
Integrated approaches to sustainable urban development: the synergy between landscape architecture and civil engineering
Get PDFThis research study addresses the developing synergy between landscape architecture and civil engineering in the context of sustainable urban development. The study intends to analyze how these multidisciplinary professions might collectively handle urban difficulties while assuring long-term environmental, social, and economic sustainability. Using the PRISMA technique, the study thoroughly reviewed secondary data from the Scopus database, identifying 23 relevant publications published between 2015 and 2024. The study outlines major integration techniques, obstacles, and emerging trends that impact the cooperation between various disciplines. The results emphasize major impediments to successful multidisciplinary collaboration, including policy fragmentation, inadequate cross-disciplinary education, and technology adaption issues. Additionally, the research underlines the significance of merging theoretical frameworks and practical case studies to increase the knowledge of integrated urban development techniques. By offering a comprehensive examination of the literature, this study adds to a greater knowledge of interdisciplinary urban planning solutions and gives significant insights for policymakers, academics, and practitioners working toward resilient and adaptable urban environments.
Article in English.
Integruotas požiūris į darnią miestų plėtrą: kraštovaizdžio architektūros ir statybos inžinerijos sinergija
Santrauka
Šiame tyrime nagrinėjama besivystanti kraštovaizdžio architektūros ir statybos inžinerijos sinergija darnios miestų plėtros kontekste. Tyrimu siekiama išanalizuoti, kaip šios daugiadisciplinės profesijos galėtų kartu spręsti miesto urbanistinius iššūkius, kartu užtikrindamos ilgalaikį aplinkos, socialinį ir ekonominį tvarumą. Taikant PRISMA metodą, tyrime išsamiai peržiūrėti antriniai duomenys iš Scopus duomenų bazės, nustatyti 23 susiję leidiniai, paskelbti 2015–2024 m. Tyrime nurodomi pagrindiniai integracijos būdai, kliūtys ir naujos tendencijos, darančios įtaką įvairių disciplinų benradarbiavimui. Rezultatuose pabrėžiamos pagrindinės sėkmingo tarpdisciplininio bendradarbiavimo kliūtys, įskaitant politikos fragmentiškumą, netinkamą tarpdisciplininį švietimą ir technologijų pritaikymo problemas. Be to, tyrime pabrėžiama teorinių pagrindų ir praktinių atvejų tyrimų sujungimo svarba siekiant pagilinti žinias apie integruotos miestų plėtros metodus. Pateikiant išsamią literatūros analizę, šis tyrimas prisideda prie gilesnių žinių apie tarpdisciplininius miestų planavimo sprendimus ir suteikia svarbių įžvalgų politikos formuotojams, mokslininkams ir praktikams, siekiantiems atsparios ir pritaikomos miestų aplinkos.
Reikšminiai žodžiai: tvarumas, miestų planavimas, kraštovaizdžio architektūra, civilinė inžinerija
Research on the composting of dog hair waste
No full textWaste management is one of the most important environmental areas for protecting the environment and human health. Biowaste decomposes and releases pollutants into the environment if left unmanaged or improperly managed. With the increasing demand for pet (especially dog) hairdressing all over the world, it is natural that the amount of discarded waste from animal fur care is also increasing. Dog hair waste can be used for the production of yarns and insulation materials, for the production of filters, and for co-posting. Composting of dog hair was chosen for the study because of its high nitrogen content and because it is one of the simplest ways to use dog hair waste. The main parameters of the composting process are analysed in the paper: C, N, ratio, pH, temperature, moisture content and electrical conductivity measurements.
Article in Lithuanian.
Šunų plaukų atliekų kompostavimo tyrimas
Atliekų tvarkymas yra viena svarbiausių aplinkosaugos sričių siekiant tausoti aplinką ir žmonių sveikatą. Biologiškai skaidžios atliekos, netvarkomos arba netinkamai tvarkomos, pūva ir į aplinką išskiria teršalus. Didėjant naminių gyvūnų (ypač šunų) kirpyklų paklausai visame pasaulyje, natūralu, kad didėja ir išmetamų gyvūnų kailio priežiūros atliekų kiekiai. Šunų plaukų atliekos gali būti naudojamos siūlų ir termoizoliacinių medžiagų gamybai, filtrų gamybai, kompostuojamos ir kt. Buvo atliktas kompostavimo tyrimas, nes šiose atliekose yra daug azoto (100 gramų plaukų yra apie 15 % azoto), taip pat tai yra vienas iš paprasčiausių būdų, kaip galima panaudoti šunų plaukų atliekas. Straipsnyje analizuojami pagrindiniai kompostavimo proceso parametrai: C, N, pH, temperatūra, drėgmė, elektrinis laidis.
Reikšminiai žodžiai: šunų plaukai, atliekos, kompostavimas, biologiškai skaidžios atliekos
Evaluating the integration of apartment building heating systems with low-temperature district heating networks
Get PDFAny renovation of apartment buildings by replacing or keeping their heating devices usually means that high temperatures of the heat carrier are maintained, which restricts boosting the efficiency of a central heating supply system. This also limits the scope for a switch to more efficient systems such as low-temperature district heating systems. To assess the impact of reducing the heat carrier temperature on indoor heating with a constant radiator area, the article investigates several alternatives alongside a base case scenario. In one scenario, the modernization of a building is examined, either by retaining the current heating devices or by substituting them with devices of equal size. Another scenario explores the modernization of a building by exchanging the heating devices and adjusting the building’s heating system to accommodate ultra-low temperatures. The possibility to reduce the temperature of the heat carrier in the heating system without any renovation of the building has been addressed as well. This led to seven alternatives. The analysis of the hourly data of the heating system model for two typical months in a heating season has revealed that when the building retains its existing area of heating devices post-renovation, the temperature can be brought down to 60/40/20 °C. It was also discovered that lowering the heat transfer temperature to ultra-low parameters (45/25/20 °C) cannot be achieved by refurbishing the buildings without increasing the number of radiators, as the heating devices will fail to deliver adequate heat for space heating.
Article in English.
Daugiabučių namų šildymo sistemų integravimo į žemos temperatūros centralizuoto šilumos tiekimo tinklus vertinimas
Santrauka
Daugiabučių namų renovacija, keičiant ar paliekant jų šildymo prietaisus, paprastai reiškia, kad reikia išlaikyti aukštą šilumnešio temperatūrą, o tai riboja centralizuoto šilumos tiekimo (CŠT) sistemos efektyvumo didinimą. Be to, tai apriboja galimybę pereiti prie efektyvesnių sistemų, pavyzdžiui, žematemperatūrių CŠT sistemų. Siekiant įvertinti sumažintos šilumnešio temperatūros poveikį patalpoms šildyti, kai radiatorių plotas išlieka pastovus, straipsnyje išnagrinėtos kelios alternatyvos ir bazinis scenarijus. Pagal vieną scenarijų nagrinėjamas pastato modernizavimas, paliekant esamus šildymo prietaisus arba pakeičiant juos tokio pat dydžio prietaisais. Pagal kitą scenarijų nagrinėjamas pastato modernizavimas pakeičiant šildymo prietaisus ir pritaikant pastato šildymo sistemą itin žemai temperatūrai. Taip pat nagrinėta galimybė sumažinti šilumnešio temperatūrą šildymo sistemoje neatnaujinant pastato. Tai leido parengti septynias alternatyvas. Išanalizavus šildymo sistemos modelio valandinius dviejų tipinių šildymo sezono mėnesių duomenis paaiškėjo, kad, po renovacijos pastate išlaikant esamą šildymo prietaisų plotą, temperatūrą galima sumažinti iki 60/40/20 °C. Taip pat nustatyta, kad renovuojant pastatus neįmanoma sumažinti šilumos perdavimo temperatūros iki itin žemų parametrų (45/25/20 °C) nekeičiant esamo radiatorių skaičiaus, nes šildymo prietaisai nesugebės tiekti pakankamai šilumos patalpoms šildyti.
Reikšminiai žodžiai: centralizuotas šilumos tiekimas (CŠT), pastatų modernizavimas, šildymo sistema, žema temperatūra
Material environment in transitional spaces: theoretical approaches and methodological directions
Get PDFThis article examines the role of material elements of the physical environment in the formation of transitional spaces, with particular attention to their impact on spatial perception and practical use. A review of the literature reveals that the materiality of transitional zones is often overlooked in architectural research, even though these spaces are increasingly recognized as significant components of the contemporary urban environment. The text also outlines the main methodological challenges encountered in systematically investigating the influence of the physical environment on the user‘s spatial experience.
Article in English.
Daiktinė aplinka pereinamosiose erdvėse: teoriniai požiūriai ir metodologinės kryptys
Santrauka
Straipsnyje nagrinėjamas materialiųjų daiktinės aplinkos elementų vaidmuo jungiamųjų erdvių formavimo procese, ypatingą dėmesį skiriant jų poveikiui erdvės suvokimui ir praktiniam naudojimui. Literatūros analizė rodo, kad pereinamųjų zonų materialumo aspektas architektūros tyrimuose dažnai lieka paraštėse, nors šios erdvės vis labiau išryškėja kaip reikšmingi šiuolaikinės urbanistinės aplinkos komponentai. Tekste taip pat išskiriami pagrindiniai metodologiniai iššūkiai, su kuriais susiduriama siekiant sistemiškai tirti daiktinės aplinkos įtaką vartotojo erdvinei patirčiai.
Reikšminiai žodžiai: daiktinė aplinka, pereinamoji erdvė, medžiagiškumas, erdvės suvokimas, vartotojo patirtis, architektūrinė artikuliacija, aplinkos psichologija
Global existence and uniqueness of mild solution for a fractional Keller-Segel system in Besov-Morrey spaces
Get PDFThis paper investigates the fractional Keller-Segel system involving both temporal and spatial variables. We examine fractional dissipation mechanisms for the physical variables, including chemotactic diffusion with fractional dissipation, and incorporate a time-fractional variation in the Caputo sense. Our analysis centers on the fractional heat semigroup, deriving time-decay and integral estimates for Mittag-Leffler operators in Besov-Morrey spaces. Furthermore, we establish a bilinear estimate arising from the nonlinearity of the Keller-Segel system, avoiding reliance on auxiliary norms. These results are then employed to demonstrate the existence and uniqueness of mild solution in Besov-Morrey spaces
Novel hybrid model for addressing uncertainty of the road safety composite indicator: integration of DEA and weighted GRA
Get PDFCreating a composite indicator is a popular concept in evaluating and comparing road safety of territories. While many other approaches are used, most current interest is on Data Envelopment Analysis (DEA) for measuring the relative performance in efficiency terms. Usefulness of DEA, which measure performance in efficiency terms, has already been proven. However, the indicators commonly used to construct a road safety composite index are not always precise and accurate (particularly safety performance indicators), and the results obtained from this type of data does not seem to be solid. So, the main aim of this paper is to represent the novel methodology to effectively evaluate the state of road safety and create a reliable composite index of the selected entities when imprecise data are involved and, to produce reliable composite index under uncertain environment. DEA, the weighting method Fan–Ma, and the Grey Relational Analysis (GRA) were integrated into hybrid methodology to obtain a more realistic and relevant picture of road safety. Applying this hybrid methodology, peculiarity of DEA is retained, scores are further differentiated, and entities are ranked and classified according to the road safety level. A case study was conducted to evaluate and rank municipalities, determine road safety classes and benchmark the territories under study. Results were verified indicating the robustness and effectiveness of the proposed methodology and its superiority to basic DEA as regards the territory ranking.
First published online 3 February 202
Location of urban logistics distribution centers considering cargo transportation services of a public transportation system
Get PDFUrban logistics distribution accounts for a large proportion of CO2 emissions generated by urban transportation. Reducing CO2 emissions in the process of logistics distribution is one of the urgent urban problems to be solved. This article investigates the location of urban logistics distribution centers considering cargo transportation services of a public transportation system. Considering one or several bus lines for representing a public transportation system, several collaborative distribution scenarios are studied, and 2 mixed integer linear programming models are established to explore the impact of the public transportation system on the location of distribution centers in urban logistics. Numerical experiments show the influence of different bus lines on the location of distribution centers, collaborative distribution and truck carbon emissions in Dalian (China). In any case, the possibility of establishing distribution centers in blocks 5 and 42 of Dalian is very high. When bus lines are used, the highest bus line utilization can reach 47.83%, and the CO2 emission can be reduced by up to 36.3%. In terms of different bus lines, line 2002 is more suitable to participate in the collaborative distribution in Dalian compared with other bus lines.
First published online 2 February 202
Assessing sustainability in BRI railway projects with a novel integrated fuzzy methodology
Get PDFChina′s Belt and Road Initiative (BRI) and South–South cooperation have received universal concern over sovereignty and debt issue, despite their goal to promote development. In Africa, the rapid expansion of Chinese-funded railway projects has overtaken the development of systematic methods for evaluating sustainability, producing a serious gap in decision-making. To address this challenge, this study proposes an integrated methodological approach, i.e., Delphi, PIvot Pairwise RElative Criteria Importance Assessment (PIPRECIA), Logarithmic Percentage Change-Driven Objective Weighting (LOPCOW), and Evaluation Based on Distance from Average Solution (EDAS) methods within the p, q Rung Orthopair Fuzzy Sets (p, q ROFSs) to assess sustainability performance under high uncertainty. The findings indicate that trade facilitation, job creation, debt sustainability, accessibility and connectivity, and safety and security are the most significant criteria for sustainability. Among the projects assessed, the Nairobi – Mombasa Standard Gauge Railway (SGR) project exhibits greatest sustainability performance, followed by the Addis Ababa – Djibouti railway while others indicated weakened outcomes because of restricted freight integration. These findings recommend that future projects should prioritize powerful trade and freight connections, guarantee employment creation and skills transfer, and implementing financing models that safeguard debt sustainability. In doing so, policymakers, managers, and planners can reinforce regional integration, improve the long-term socio-economic advantages, and obtain the operational and financial viability of extensive railway investments in Africa