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Authors - 9811
Ismael Campos-Nonato
57203424784
Karahan Kara
57480381600
Tetyana Vasilyeva
58921823400
Fazeel Mahmood Khan
36835760100
Publications - 6374
Parametric Investigation of Interaction between Soil-Surface Structure and Twin Tunnel Excavation: A Comprehensive 2D Numerical Study
Publication Name: Infrastructures
Publication Date: 2023-08-01
Volume: 8
Issue: 8
Page Range: Unknown
Description:
The growing demand for transportation tunnels in densely populated urban areas has led to the widespread adoption of twin tunnel configurations in contemporary infrastructure projects. This research focuses on investigating the complex interaction between soil, structures, and the excavation of twin tunnels. The study employs the tunnel boring machine (TBM) method and utilizes two-dimensional numerical modeling based on the finite element method (FEM). The numerical model is validated by comparing its results with field measurements obtained from a twin tunnel project in Italy, specifically the New Milan Metro Line 5. A comprehensive parametric study is conducted to analyze various parameters that influence soil–structure interaction during tunnel excavation. These parameters include the positioning of the tunnels in relation to each other, the spacing between them, the presence of structures above the tunnels, eccentricity between the structure axis and tunnel axis, and tunnel depth and diameter. Moreover, a comparative analysis is performed between scenarios with and without structures to elucidate the impact of structure presence on the interaction phenomenon. The research findings provide valuable insights into the intricate behavior of twin tunnels and their interaction with the surrounding soil and structures.
Open Access: Yes
Error estimation of wavelet based modeling of electromagnetic waves in waveguides and resonators
Publication Name: 2nd Middle East Conference on Antennas and Propagation Mecap 2013
Publication Date: 2012-01-01
Volume: Unknown
Issue: Unknown
Page Range: Unknown
Description:
Wavelets provide an effective toolbox for solving differential equations by representing the continuous functions by their wavelet expansion coefficients and the corresponding differential equations by discrete matrix equations. The wavelet basis functions are organized into resolution levels of different frequency terms at different locations, and the main advantage of the wavelet expansion representation is that the resolution level can be different at different locations, if the solution function contains higher frequency terms in one place and restricted to lower frequencies at other places. Wavelet based differential equation solving methods can be adaptive, it is possible to refine the solution locally, if the precision is not sufficient at some regions. In the present work a simple method for estimating the next resolution level wavelet coefficients is presented. Predicting the approximate value of these coefficients makes it possible to select the minimal set of wavelet basis functions for the next resolution level solution in a computationally economic way, or in the last resolution levels it can substitute the next level solution of the matrix equation. © 2012 IEEE.
Open Access: Yes
Analysis of socio-economic spatial structure of urban agglomeration in China based on spatial gradient and clustering
Publication Name: Oeconomia Copernicana
Publication Date: 2021-09-01
Volume: 12
Issue: 3
Page Range: 789-819
Description:
Research background: Previous studies on the economic and social development of urban agglomerations mostly focus on a single primacy comparative analysis and efficiency evaluation. Spatial structure differentiation is an important feature of urban agglomeration. The lack of economic and social analysis on the spatial structure makes it impossible to determine the development positioning of each city in the urban agglomeration, which affects the sustainable economic devel-opment ability of these areas. Purpose of the article: The objective of the article is to analyze the spatial development law and experience of urban agglomeration, this study explores the practice of economic and population spatial structure of city areas in China. For this purpose, CPUA and its central city Zhengzhou was taken as an example, the spatial gradient structure of example was analyzed. Methods: Using economic and population data of 32 cities in this region, growth pole theory, and pole-axis theory, the economic and population spatial structure of urban agglomeration, the spatial gradient structure of central cities in urban agglomerations were analyzed with the method of cluster about radiation index. Findings & value added: (1) In the process of the formation of CPUA, the geo-graphical spatial pattern plays a decisive role in economic and social development. This is an experience from developing countries. (2) CPUA presents a gradient development pattern with Zhengzhou as the center, and economic and social development gradually radiates to the metropolitan area, the core development area, and the character development demonstration area. (3) The economic and social gradients of Zhengzhou, the central city, present the hierarchy rules and characteristics which are driven by the Beijing-Guangzhou-Railway axis and the Longhai-Railway axis. (4) The central city of Zhengzhou still presents insufficient primacy in regional development, which shows that Zhengzhou accounts for 6% of the population of the Central Plains Economic Zone and 14% of GDP, and insufficient agglomeration. Different countries at different stages of economic development have different urban agglomeration development models. The conclusions from China provide new decision-making ideas and methods for spatial structure research and development strategy analysis of urban agglomerations.
Open Access: Yes
DOI: 10.24136/OC.2021.026
Tribological investigation of the effect of nanosized CuO and TiO2 on a base oil containing Komad 323 dispersant
Publication Name: Jurnal Tribologi
Publication Date: 2024-09-01
Volume: 42
Issue: Unknown
Page Range: 103-128
Description:
This article investigates the impact of copper(II) oxide (CuO) and titanium dioxide (TiO2 ) nanoparticles in Group III base oil with 8 wt% Komad 323 dispersant. Nanoparticles underwent ethyl oleate surface modification. Tribological properties were assessed using a linear oscillating tribometer, continuously monitoring static friction. Friction integral values were derived from extensive data acquisition. Wear analysis employed digital optical and confocal microscopy, complemented by scanning electron microscopy for wear-type characterization and energy-dispersive X-ray spectroscopy for additive quantification in the wear track. Results indicate CuO nanoparticles' poor compatibility with Komad 323, resulting in increased friction (2-13%) and substantial wear reduction (39-50%) at low CuO concentrations (≤0.3 wt%). Higher concentrations (≥0.4 wt%) reduced friction (21-35%) but led to surface fatigue and increased wear rates. Elemental composition analysis of the wear track revealed that the surface contains 1.43-3.17 norm.wt% copper. Conversely, TiO2 in synergy with the dispersant, formed a boundary layer, exhibiting lower friction by 11-14%. TiO2 formed a high wear resistance boundary layer at titanium concentrations of 0.33-0.39 norm.wt%, which resulted in 44% wear volume reduction. Applying both nanoparticles reduced the wear scar diameter of the test specimens by 3-12%.
Open Access: Yes
DOI: DOI not available
Transferring and scaling innovation in urban green-blue Infrastructure: beyond one-size-fits-all solutions and preconceptions
Publication Name: Sustainable Futures
Publication Date: 2026-06-01
Volume: 11
Issue: Unknown
Page Range: Unknown
Description:
Green and Blue Infrastructure (GBI) innovations are increasingly promoted in Europe, yet their transfer to new socio-political contexts remains poorly understood. This study applies the Strategic Niche Management (SNM) framework to analyse the conditions under which GBI innovations can be replicated and scaled beyond their original settings. We examine six GBI projects from five EU Member States and assess their perceived transferability through three expert workshops in Belarus, Russia and Ukraine. Using a comparative qualitative design, workshop transcripts were analysed to identify how actors interpret innovation, allocate responsibilities, and negotiate risks within their socio-technical regimes. Across cases, successful transfer depended on leadership by municipal actors, a supportive knowledge base, flexible regulatory arrangements, and targeted communication that strengthens public acceptance. Major constraints included entrenched “business-as-usual’’ routines in administrative and epistemic communities, misconceptions about the costs and maintenance of GBI, weak participatory traditions, and corruption risks. The findings demonstrate that GBI diffusion is highly context-dependent: local actors may be unexpectedly supportive of nature-based solutions, while bottom-up initiatives can serve as viable entry points even within hierarchical governance systems. The study contributes empirical insights from an under-researched region and illustrates how SNM can be operationalised to guide GBI innovation transfer and regime change.
Open Access: Yes
Variations of gravitation models using geometric programming
Publication Name: Isciii 2011 5th International Symposium on Computational Intelligence and Intelligent Informatics
Publication Date: 2011-12-12
Volume: Unknown
Issue: Unknown
Page Range: 93-97
Description:
The article deals with the gravitation problem, which is widely used for solving different practical problems. First of all it is used to forecast the future traffic of a territory (Origin/destination problem). It is also used in the economy for forecasting the Leontief Input/Output table. It will be shown if the I-divergence is used for the sample O/D matrix and the future traffic matrix the cost function is exponential and the element of the forecasted matrix are determined in the well known RAS form. For the proof the geometric programming and its dual and the week and strong duality theorem are applied. © 2011 IEEE.
Open Access: Yes
Strategic management, scenario analysis and competitive advantage analysis: New opportunities for anti-money laundering system reform
Publication Name: E A M Ekonomie A Management
Publication Date: 2023-01-01
Volume: 26
Issue: 2
Page Range: 140-157
Description:
The article identifies and mathematically substantiates vectors of reforming the financial monitoring system based on the synergistic approach in the cross-country context by developing scenarios by selecting internal and external factors that stimulate money laundering. The key external and internal factors of the money laundering process intensification are indicated. Competitive advantages of the anti-money laundering processes, the achievement of which is possible in terms of key external and internal factors for activation of money laundering process are formed. The relationship between the key internal and external factors of money laundering intensification and competitive advantages by building a binary characteristic matrix is formed. The synergy effect made by the mutual influence of simultaneously acting internal and external factors – a quantitative feature of the further strategy of the financial monitoring system reforming in terms of cross-country analysis is calculated. An economic-mathematical model for evaluating and interpreting strategy for improving the financial monitoring system in terms of cross-country context based on integer optimization is developed. In the article, there is calculation of the number of competitive advantages received by each observed country, without considering the possible synergy effect of mutual influence of simultaneously acting internal and external factors on each other. Moreover, there is quantitative assessment of the synergy effect made by the emergence of additional competitive advantages due to a certain combination of simultaneous influence made by external and internal factors of the money laundering intensification. The “ideal” situation of the possibility of gaining all possible competitive advantages in reforming the financial monitoring system in terms of cross-country context by overcoming internal and external factors stimulating the money laundering is studied. The results of the cross-country analysis form a basis for the further formalization of the limits for quantitative evaluation of the developed strategies through a uniform distribution.
Open Access: Yes
Node embeddings in dynamic graphs
Publication Name: Applied Network Science
Publication Date: 2019-12-01
Volume: 4
Issue: 1
Page Range: Unknown
Description:
In this paper, we present algorithms that learn and update temporal node embeddings on the fly for tracking and measuring node similarity over time in graph streams. Recently, several representation learning methods have been proposed that are capable of embedding nodes in a vector space in a way that captures the network structure. Most of the known techniques extract embeddings from static graph snapshots. By contrast, modeling the dynamics of the nodes in temporal networks requires evolving node representations. In order to update node representations that reflect the temporal changes in the local graph structure, we rely on ideas for data stream algorithms. For example, we assess neighborhood overlap by a MinHash fingerprint-based algorithm. To evaluate our methods, in addition to the standard link prediction task, we provide dynamic ground truth data for the quantitative evaluation of similarity search by using online updated node embeddings. In our experiments, we constructed tennis tournament Twitter mention graphs as edge streams and compiled dynamic ground truth by using tournament schedule as external source. Our new algorithms outperformed snapshot-based batch methods for both link prediction and similarity search.
Open Access: Yes
Sorting for Sustainability: Harnessing Female Awareness of Zero Waste
Publication Name: Journal of Sustainability Research
Publication Date: 2024-12-01
Volume: 6
Issue: 4
Page Range: Unknown
Description:
Background: Sustainable Development Goal 12 focuses on sustainable consumption and production patterns. Females are more likely to adopt these sustainable consumption practices due to their environmental attitudes. The scope of the present research is to develop a Hungarian model that can provide a theoretical explanation for the formation, viability and empowerment of zero waste awareness among females as they are sensitive to the issue and may have sufficient knowledge about it. Methods: An online questionnaire was distributed in a university environment in Hungary, resulting in 160 responses after data cleaning. The model was constructed using Partial Least Squares Structural Equation Modelling (PLS-SEM). Results: The results show that for females, the factors waste sorting and zero waste practicality account for 72.4% of the variance in zero waste awareness. The Beta values indicate that both effects are positive with the effect of the first (βZWS-ZWA = 0.523) being stronger than the second (βZWP-ZWA = 0.389). In addition, it can be concluded that women’s attitudes toward waste sorting have a strong positive impact (R2 = 0.542, βZWS-ZWP = 0.736) on zero waste practicality. Conclusions: The zero waste attitudes of female university students’ behavior are significantly related to the selective collection of waste and the practical use of old products. In addition, waste separation is a practical approach to environmental responsibility, as there is no need to dispose of all end-of-life products if they can be recycled. The model could help the government understand the factors and the mindset from a female perspective in order to partially support the decision-making process related to sustainability.
Open Access: Yes
