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  • 1.
    Abdullah Abkar, Mahdi Mohammed
    et al.
    Faculty of Civil Engineering and Built Environment Universiti Tun Hussein Onn Malaysia (UTHM) Parit Raja, Batu Pahat, Johor, 86400, Malaysia.
    Yunus, Riduan
    Faculty of Civil Engineering and Built Environment Universiti Tun Hussein Onn Malaysia (UTHM) Parit Raja, Batu Pahat, Johor, 86400, Malaysia.
    Gamil, Yaser
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. Department of Civil Engineering, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia.
    Albaom, Mohammed Abdo
    Faculty of Computer Science and Information Technology, Department of Computer Science, Universiti Putra Malaysia, Serdang 43400, Malaysia.
    Enhancing construction site performance through technology and management practices as material waste mitigation in the Malaysian construction industry2024Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 10, nr 7, artikel-id e28721Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The construction industry, increasingly prioritizing sustainability, necessitates an exploration of technology and management's role in mitigating material waste at construction sites. This study examines the impact of 3R, IBS, BIM, and MMA in enhancing Construction Site Performance (CSP) in the Malaysian construction sector. Seven hypotheses were formulated to assess the relationship between technology adoption, material management practices, and the moderating influence of Material Management Adoption (MMA) on CSP. Data were collected through an online survey from 295 valid responses in the Malaysian construction sector, focusing on professionals involved in solid waste management. Utilizing Partial Least Squares - Structural Equation Modeling (PLS-SEM) and Statistical Package for the Social Sciences (SPSS), the findings highlight the importance of technological integration, efficient material management, and competitive strategies in effective material waste mitigation. Furthermore, the qualitative aspect of the study, conducted among 6 solid waste organizations in Malaysia, enriches the findings by providing nuanced insights into local practices and challenges. Emphasizing the importance of contextual insights, the study addresses professionals involved in solid waste management within the Malaysian construction industry. The geographical specificity adds depth to the analysis, offering a comprehensive understanding of regional dynamics. Despite acknowledging limitations in technology and material usage, the study offers recommendations for refining waste mitigation and improving construction site performance. This research model offers actionable insights for construction site stakeholders, emphasizing the criticality of waste mitigation and CSP. The results, both quantitative and qualitative, underscore the potential of these practices within the Malaysian construction industry to foster innovation and drive positive change.

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  • 2.
    Agrawal, Dhiraj
    et al.
    Department of Civil Engineering, Yeshwantrao Chavan College of Engineering, Hingna Road, Wanadongri, Nagpur, 441110, India.
    Waghe, Uday
    Department of Civil Engineering, Yeshwantrao Chavan College of Engineering, Hingna Road, Wanadongri, Nagpur, 441110, India.
    Ansari, Khalid
    Department of Civil Engineering, Yeshwantrao Chavan College of Engineering, Hingna Road, Wanadongri, Nagpur, 441110, India.
    Amran, Mugahed
    Department of Civil Engineering, College of Engineering, Prince Sattam Bin Abdulaziz University, 11942, Alkharj, Saudi Arabia; Department of Civil Engineering, Faculty of Engineering and IT, Amran University, 9677, Amran, Yemen.
    Gamil, Yaser
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. Department of Civil Eng., School of Eng., Monash University Malaysia, Jalan Lagoon Selatan, 47500, Sunway, Selangor, Malaysia.
    Alluqmani, Ayed E.
    Department of Civil Engineering, Islamic University of Madinah, Madinah, 41411, Saudi Arabia.
    Thakare, Nitin
    Department of Civil Engineering, G. H. Raisoni Institute of Engineering and Technology, Nagpur, 441110, India.
    Optimization of eco-friendly concrete with recycled coarse aggregates and rubber particles as sustainable industrial byproducts for construction practices2024Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 10, nr 4, artikel-id e25923Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this technology era, sustainable construction practices have become quite imperative. The exploration of alternative materials to reduce the environmental footprint is of paramount importance. This research paper delves into an exhaustive investigation concerning the utilization of recycled coarse aggregates (RCA) and rubber particles (RP) in concrete. It contributes to the growing body of knowledge aimed at fostering sustainable development in the construction industry by reducing waste, promoting recycling, and mitigating the environmental footprint of building materials. The objective of the study is to evaluate the potential benefits and limitations associated with incorporating these materials, thereby providing a sustainable alternative to conventional concrete. In this research, construction and demolition waste were recycled and used as RCA as a fractional switch of natural coarse aggregate (NCA) from 0% to 100%, with an increment of 20% replacement of NCA in concrete. The RP received from discarded tires generated as automobile industry waste were used as a volumetric fractional substitution of sand in concrete from 0% to 20%, with a 5% increment. No pre-treatment for RCA and RP was carried out before their utilization in concrete. A total of 26 mixes, including control concrete without NCA and RP, with a design strength of 40 MPa, were prepared and tested. Concrete mixes were examined for workability, density, mechanical, and durability properties. It was found that the concrete with 60% RCA and 10% RP showed satisfactory results in evaluation with the strength parameters of control concrete, as the compressive strength obtained for this concrete mix is 40.18 MPa, similar to the control mix. The optimization for RCA and RP was conducted using Response Surface Methodology (RSM). The major concern observed was a rise in water absorption with an increase in the percentage replacement of NCA and natural sand by RCA and RP. Findings from the investigation illustrate a promising prospect for the use of RCA and RP in concrete applications, displaying competent mechanical properties and enhanced durability under certain conditions, offering a viable option for environmentally friendly construction practices. However, the research also sheds light on some constraints and challenges, such as the variability in the quality of RCA and the necessity for meticulous quality control to ensure the reliability and consistency of the end product. It is discerned that further refinement in processing techniques and quality assurance measures is pivotal for mainstream adoption of RCA and RP in concrete construction.

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  • 3.
    Alsaffar, Abdul Kareem K.
    et al.
    Engineering Faculty, University of Babylon, Babylon, Iraq.
    Alquzweeni, Saif S.
    Engineering Faculty, University of Babylon, Babylon, Iraq.
    Al-Ameer, Lubna R.
    Al-Zahraa University for Women, Kerbala, Iraq.
    Ali, Abduljabar H.
    Mechanical Engineering, Al-Mustaqbal University, Al-Hillah, Iraq.
    Mohamed, Ahmed
    School of Civil Engineering and Built Environment, Liverpool John Moores University, Liverpool, L3 3AF, UK.
    Aldaihani, Humoud M.
    Geotechnical and Geoenvironmental Engineering, Implementation Construction Sector, Public Authority for Housing Welfare, Kuwait.
    Reham, A.
    Engineering Faculty, University of Babylon, Babylon, Iraq.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Al-Hashimi, Osamah
    School of Civil Engineering and Built Environment, Liverpool John Moores University, Liverpool, L3 3AF, UK.
    Shubbar, Ali
    School of Civil Engineering and Built Environment, Liverpool John Moores University, Liverpool, L3 3AF, UK.
    Khan, Mohammad Amir
    Department of Civil Engineering, Galgotias College of Engineering, Greater Noida, 201310, India.
    Hashim, Khalid
    School of Civil Engineering and Built Environment, Liverpool John Moores University, Liverpool, L3 3AF, UK.
    Development of eco-friendly wall insulation layer utilising the wastes of the packing industry2023Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 9, nr 11, artikel-id e21799Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Efficient thermal insulation materials considerably lower power consumption for heating and cooling of buildings, which in turn minimises CO2 emissions and improves indoor comfort conditions. However, the selection of suitable insulation materials is governed by several factors, such as the environmental impact, health impact, cost and durability. Additionally, the disposal of used insulation materials is a major factor that affects the selection of materials because some materials could be very toxic for humans and the environment, such as asbestos-containing materials. Therefore, there is a continuous research effort, in both industry and academia, to develop sustainable and affordable insulation materials. In this context, this work aims at utilising the packing industry wastes (cardboard) to develop an eco-friendly insulation layer, which is a biodegradable material that can be disposed of safely after use. Experimentally, wasted cardboard was collected, cleaned, and soaked in water for 24 h. Then, the wet cardboard was minced and converted into past papers, then cast in square moulds and left in a ventilated oven at 75 °C to dry before de-moulding them. The produced layers were subjected to a wide range of tests, including thermal conductivity, acoustic insulation, infrared imaging and bending resistance. The obtained results showed the developed material has a good thermal and acoustic insulation performance. Thermally, the developed material had the lowest thermal conductivity (λ) (0.039 W/m.K) compared to the studied traditional materials. Additionally, it successfully decreased the noise level from 80 to about 58 dB, which was better than the efficiency of the commercial polyisocyanurate layer. However, the bending strength of the developed material was a major drawback because the material did not resist more than 0.6 MPa compared to 2.0 MPa for the commercial polyisocyanurate and 70.0 MPa for the wood boards. Therefore, it is recommended to investigate the possibility of strengthening the new material by adding fibres or cementitious materials.

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  • 4.
    Baromand, Salman
    et al.
    Department of Electrical Engineering, Fasa University, Fasa, Iran.
    Zaman, Amirreza
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Signaler och system.
    Mihaylova, Lyudmila
    Department of Automatic Control and Systems Engineering, University of Sheffield, Sheffield, UK.
    Trust-based fault detection and robust fault-tolerant control of uncertain cyber-physical systems against time-delay injection attacks2021Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 7, nr 6, artikel-id e07294Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Control systems need to be able to operate under uncertainty and especially under attacks. To address such challenges, this paper formulates the solution of robust control for uncertain systems under time-varying and unknown time-delay attacks in cyber-physical systems (CPSs). A novel control method able to deal with thwart time-delay attacks on closed-loop control systems is proposed. Using a descriptor model and an appropriate Lyapunov functional, sufficient conditions for closed-loop stability are derived based on linear matrix inequalities (LMIs). A design procedure is proposed to obtain an optimal state feedback control gain such that the uncertain system can be resistant under an injection time-delay attack with variable delay. Furthermore, various fault detection frameworks are proposed by following the dynamics of the measured data at the system's input and output using statistical analysis such as correlation analysis and K-L (Kullback-Leibler) divergence criteria to detect attack's existence and to prevent possible instability. Finally, an example is provided to evaluate the proposed design method's effectiveness.

  • 5. Bergamo, Pedro A. de S.
    Minfloat - Gamified learning in minerals engineeringIngår i: Heliyon, E-ISSN 2405-8440Artikel i tidskrift (Refereegranskat)
  • 6.
    Berglund, Leif
    et al.
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Människa och teknik.
    Johansson, Jan
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Människa och teknik.
    Johansson, Maria
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Människa och teknik.
    Nygren, Magnus
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Människa och teknik.
    Stenberg, Magnus
    Luleå tekniska universitet, Institutionen för ekonomi, teknik, konst och samhälle, Människa och teknik.
    Safety culture development in the construction industry: The case of a safety park in Sweden2023Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 9, nr 9, artikel-id e18679Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The problem of occupational accidents in the construction industry has necessitated a focus on proactive measures such as safety management programs. An example of this is safety parks, i.e. facilities where employees and managers from different construction companies can participate in site-specific activities and train in safety-related matters in a realistic context. Two specific focus areas are often present within these types of safety management programs: hands-on safety training and safety culture development as being within the purview of management. The purpose of this article is to investigate the developers’ intentions with the park in relation to safety culture development. Twenty interviews were conducted with experts in the area of health and safety. Results indicate that the safety park can contribute as a mirror for the companies own operations, with new information and knowledge of how work can be performed with safety being prioritized, to developing communication regarding safety-related matters, and finally the stations at the park may initiate a translation process as to how the lessons learned at the park can be applied to the participants’ own workplaces. All in all, the activities at the park can be said to be normative in nature, i.e. the developers seemingly have a desire to steer the safety culture development in a certain direction. There is a need for further research focusing on the concept of safety culture in these types of programs and, more broadly, in relation to its intended industry-wide effects.

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  • 7.
    Bhutto, Shahzeb
    et al.
    Department of Civil Engineering, Mehran University of Engineering and Technology, Jamshoro 76090, Sindh, Pakistan.
    Abro, Fahad-ul-Rehman
    Department of Civil Engineering, Mehran University of Engineering and Technology, Jamshoro 76090, Sindh, Pakistan.
    Ali, Mohsin
    Graduate School of Urban Innovation, Department of Civil Engineering, Yokohama National University, Kanagawa, 240-8501, Japan.
    Buller, Abdul Salam
    Department of Civil Engineering, NED University Constitute College Thar Institute of Engineering, Science and Technology, 69230, Mithi, Tharparkar, Sindh, Pakistan.
    Bheel, Naraindas
    Department of Civil and Environmental Engineering, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Tronoh, Perak, 32610, Malaysia.
    Gamil, Yaser
    Department of Civil Engineering, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia.
    Najeh, Taoufik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Deifalla, Ahmed Farouk
    Structural Engineering and Construction Management Department, Future University in Egypt, 11835, New Cairo, Egypt.
    Ragab, Adham E.
    Department of Industrial Engineering, College of Engineering, King Saud University, P.O. Box 800, Riyadh 11421, Saudi Arabia.
    Almujibah, Hamad R.
    Department of Civil Engineering, College of Engineering, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia.
    Effect of banana tree leaves ash as cementitious material on the durability of concrete against sulphate and acid attacks2024Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 10, nr 7, artikel-id e29236Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The construction industry's rapid growth poses challenges tied to raw material depletion and increased greenhouse gas emissions. To address this, alternative materials like agricultural residues are gaining prominence due to their potential to reduce carbon emissions and waste generation. In this context this research optimizes the use of banana leaves ash as a partial cement substitution, focusing on durability, and identifying the ideal cement-to-ash ratio for sustainable concrete. For this purpose, concrete mixes were prepared with BLA replacing cement partially in different proportions i.e. (0 %, 5 %, 10 %, 15 %, & 20 %) and were analyzed for their physical, mechanical and Durability (Acid and Sulphate resistance) properties. Compressive strength, acid resistance and sulphate resistance testing continued for 90 days with the intervals of 7, 28 and 90 days. The results revealed that up to 10 % incorporation of BLA improved compressive strength by 10 %, while higher BLA proportions (up to 20 %) displayed superior performance in durability tests as compared to the conventional mix. The results reveal the potentials of banana leave ash to refine the concrete matrix by formation of addition C–S–H gel which leads towards a better performance specially in terms of durability aspect. Hence, banana leaf ash (BLA) is an efficient concrete ingredient, particularly up to 10 % of the mix. Beyond this threshold, it's still suitable for applications where extreme strength isn't the primary concern, because there may be a slight reduction in compressive strength.

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  • 8.
    Ehsan, Muhsan
    et al.
    Department of Earth and Environmental Sciences, Bahria School of Engineering and Applied Sciences, Bahria University, Islamabad, 44000, Pakistan.
    Toor, Muhammad Arslan Shakeel
    Department of Earth and Environmental Sciences, Bahria School of Engineering and Applied Sciences, Bahria University, Islamabad, 44000, Pakistan.
    Hajana, Muhammad Iqbal
    Department of Earth and Environmental Sciences, Bahria School of Engineering and Applied Sciences, Bahria University, Islamabad, 44000, Pakistan.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Ali, Amjad
    School of Earth Sciences, Zhejiang University, Hangzhou, Zhejiang, China.
    Elbeltagi, Ahmed
    Agricultural Engineering Dept., Faculty of Agriculture, Mansoura University, Mansoura 35516, Egypt.
    An integrated study for seismic structural interpretation and reservoir estimation of Sawan gas field, Lower Indus Basin, Pakistan2023Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 9, nr 5, artikel-id e15621Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The information about the subsurface structure, type of fluids present in the reservoir, and physical properties of the rocks is essential for identifying potential leads. The integrated approach of petrophysical analysis, seismic data interpretation, seismic attributes analysis, lithology, mineralogy identification, and Gassmann fluid substitution were used for this purpose. The structural interpretation with the help of seismic data indicated the extensional regime with horst and graben structures in the study area. The two negative flower structures are cutting the entire Cretaceous deposits. The depth contour map also indicate favorable structures for hydrocarbon accumulation. The four possible reservoir zones in the Sawan-01 well and two zones in the Judge-01 well at B sand and C sand levels are identified based on well data interpretation. The main lithology of the Lower Goru Formation is sandstone with thin beds of shale. The clay types confirm the marine depositional environment for Lower Goru Formation. The water substitution in the reservoir at B sand and C sand levels indicated increased P-wave velocity and density. The water substitution affected the shear wave velocity varies slightly due to density changes. The cross plots of P-impedance versus Vp/Vs ratio differentiate the sandstone with low P-impedance and low Vp/Vs ratio from shaly sandstone with high values in the reservoir area. The P-impedance and S-impedance cross plot indicate increasing gas saturation with a decrease in impedance values. The low values of Lambda-Rho and Mu-Rho indicated the gas sandstone in the cross plot.

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  • 9.
    Fischer, Robert
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Toffolo, Andrea
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Game theory-based analysis of policy instrument consequences on energy system actors in a Nordic municipality2024Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 10, nr 4, artikel-id e25822Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The transition of energy systems requires policy frameworks and instruments to make both energy suppliers and consumers contribute to the common goal of emission reductions and to fairly allocate costs and benefits among market actors and the government. Assuming that market actors – suppliers and consumers adhering to their economic interests – would benefit from cooperating to mitigate emissions, this study applies a game theory-based approach to investigate the interaction between a local electricity supplier and a group of heating consumers not connected to district heating. Selected policy instruments are tested, and their consequences are analyzed in the context of a representative Nordic municipality. The results show that the auction-based Contract for Difference policy instrument is the most suitable one in the studied Nordic context to achieve significant levels of CO2 emissions reduction. It creates a higher level of strategic interaction between the actors, that would be lacking otherwise, under the form of transfer payments from consumers to supplier, and avoids costs to the general taxpayer. While this is sufficient to promote the investments in renewables by the supplier, additional subsidy policies are required to enable the heating consumers to invest in more capital-intensive energy efficiency measures or biomass heating.

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  • 10.
    Gorai, Priya Kumari
    et al.
    Department of Anatomy, All India Institute of Medical Sciences, New Delhi, India.
    Rastogi, Simran
    Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India.
    Bharti, Prahalad Singh
    Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India.
    Agarwal, Shipra
    Department of Pathology, All India Institute of Medical Sciences, New Delhi, India.
    Pal, Sujoy
    Department of GI Surgery, All India Institute of Medical Sciences, New Delhi, India.
    Sharma, Mehar Chand
    Department of Pathology, All India Institute of Medical Sciences, New Delhi, India.
    Kumar, Rakesh
    Department of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, India.
    Nikolajeff, Fredrik
    Luleå tekniska universitet, Institutionen för hälsa, lärande och teknik, Omvårdnad och medicinsk teknik.
    Kumar, Saroj
    Luleå tekniska universitet, Institutionen för hälsa, lärande och teknik, Omvårdnad och medicinsk teknik. Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India.
    Rani, Neerja
    Department of Anatomy, All India Institute of Medical Sciences, New Delhi, India.
    Deciphering pancreatic neuroendocrine tumors: Unveiling through circulating small extracellular vesicles2024Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 10, nr 7, artikel-id e29079Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The survival rate over a five-year period for rare pancreatic neuroendocrine tumors (PanNET) is notably lower compared to other neuroendocrine tumors due to late-stage detection, which is a consequence of the absence of suitable diagnostic markers; therefore, there exists a critical need for an early-stage biomarker-specific to PanNETs. This study introduces a novel approach, investigating the impact of small extracellular vesicles (sEV) in PanNET growth and metastasis. As proof of concept, this study shows a correlation between sEV concentration in controls and PanNET. Notably, higher sEV concentrations were observed in PanNETs than in controls (p < 0.0001) with a sensitivity of 100%. Further, apparent differences were observed in the sEV concentrations between controls and grades 1 PanNET (p = 0.005). The expression of sEV markers was confirmed using CD63, TSG101, CD9, Flotillin-1, and GAD65 antibodies. Additionally, the expression of cancer marker BIRC2/cIAP1 (p = 0.002) and autophagy marker Beclin-1 (p = 0.02) were observed in plasma-derived sEVs and PanNET tissue. This study represents the first to indicate the increased secretion of sEV in PanNET patients&apos; blood plasma, proposing potential function of sEV as a new biomarker for early-stage PanNET detection.

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  • 11.
    Habib, Nudrat
    et al.
    Department of Computer Science, COMSATS University Islamabad, Abbottabad Campus, Abbottabad, Pakistan.
    Saqib, Muhammad
    Department of Civil Engineering, COMSATS University Islamabad, Abbottabad Campus, Abbottabad, Pakistan.
    Najeh, Taoufik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Gamil, Yaser
    Department of Civil Engineering, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia.
    Eco-Transformation of construction: Harnessing machine learning and SHAP for crumb rubber concrete sustainability2024Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 10, nr 5, artikel-id e26927Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Researchers have focused their efforts on investigating the integration of crumb rubber as a substitute for conventional aggregates and cement in concrete. Nevertheless, the manufacture of crumb rubber concrete (CRC) has been linked to the release of noxious pollutants, hence presenting potential environmental hazards. Rather than developing novel CRC formulations, the primary objective of this work is to construct an extensive database by leveraging prior research efforts. The study places particular emphasis on two crucial concrete properties: compressive strength (fc') and tensile strength (fts). The database includes a total of 456 data points for fc&apos; and 358 data points for fts, focusing on nine essential characteristics that have a substantial impact on both attributes. The research employs several machine learning algorithms, including both individual and ensemble methods, to undertake a comprehensive analysis of the created databases for fc&apos; and fts. In order to ascertain the correctness of the models, a comparative analysis of machine learning techniques, namely decision tree (DT) and random forest (RF), is conducted using statistical evaluation. Cross-validation approaches are used in order to address the possible issues of overfitting. Furthermore, the Shapley additive explanations (SHAP) approach is used to investigate the influence of input parameters and their interrelationships. The findings demonstrate that the RF methodology has superior performance compared to other ensemble techniques, as shown by its lower error rates and higher coefficient of determination (R2) of 0.87 and 0.85 for fc'; and fts respectively. When comparing ensemble approaches, it can be seen that AdaBoost outperforms bagging by 6 % for both outcome models and individual decision tree learners by 17% and 21% for fc'; and fts respectively in terms of performance. The average accuracy of AdaBoost algorithm for both the models is 84%. Significantly, the age and the inclusion of crumb rubber in CRC are identified as the primary criteria that have a substantial influence on the mechanical properties of this particular kind of concrete.

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  • 12.
    Iftikhar, Bawar
    et al.
    School of Civil Engineering, Universiti Teknologi Malaysia, 81310, Johor Bahru Johor, Malaysia; Department of Civil Engineering, COMSATS University Islamabad, Abbottabad Campus 22060, Pakistan.
    Alih, Sophia C.
    Institute of Noise and Vibration, School of Civil Engineering, Universiti Teknologi Malaysia, 81310, Johor Bahru Johor, Malaysia.
    Vafaei, Mohammadreza
    School of Civil Engineering, Universiti Teknologi Malaysia, 81310, Johor Bahru Johor, Malaysia.
    Ali, Mujahid
    Department of Transport Systems, Traffic Engineering and Logistics, Silesian University of Technology, Krasinskiego 8 Street, Katowice, Poland.
    Javed, Muhammad Faisal
    Department of Civil Engineering, COMSATS University Islamabad, Abbottabad Campus 22060, Pakistan.
    Asif, Usama
    Department of Civil Engineering, COMSATS University Islamabad, Abbottabad Campus 22060, Pakistan.
    Ismail, Muhammad
    Department of Civil Engineering, COMSATS University Islamabad, Abbottabad Campus 22060, Pakistan.
    Umer, Muhammad
    Department of Civil Engineering, COMSATS University Islamabad, Abbottabad Campus 22060, Pakistan.
    Gamil, Yaser
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. Department of Civil Engineering, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia.
    Amran, Mugahed
    Department of Civil Engineering, College of Engineering, Prince Sattam Bin Abdulaziz University, 11942, Alkharj, Saudi Arabia; Department of Civil Engineering, Amran University, 9677, Amran, Yemen.
    Experimental study on the eco-friendly plastic-sand paver blocks by utilising plastic waste and basalt fibers2023Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 9, nr 6, artikel-id e17107Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Plastic waste poses a significant hazard to the environment as a result of its high production rates, which endanger both the environment and its inhabitants. Similarly, another concern is the production of cement, which accounts for roughly 8% of global CO2 emissions. Thus, recycling plastic waste as a replacement for cementitious materials may be a more effective strategy for waste minimisation and cement elimination. Therefore, in this study, plastic waste (low-density polyethylene) is utilised in the production of plastic sand paver blocks without the use of cement. In addition to this, basalt fibers which is a green industrial material is also added in the production of eco-friendly plastic sand paver blocks to satisfy the standard of ASTM C902-15 of 20 N/mm2 for the light traffic. In order to make the paver blocks, the LDPE waste plastic was melted outside in the open air and then combined with sand. Variations were made to the ratio of LDPE to sand, the proportion of basalt fibers, and sand particle size. Paver blocks were evaluated for their compressive strength, water absorption, and at different temperatures. Including 0.5% percent basalt fiber of length 4 mm gives us the best result by enhancing compressive strength by 20.5% and decreasing water absorption by 50.5%. The best results were obtained with a ratio of 30:70 LDPE to sand, while the finest sand provides the greatest compressive strength. Moreover, the temperature effect was also studied from 0 to 60 °C, and the basalt fibers incorporated in plastic paver blocks showed only a 20% decrease in compressive strength at 60 °C. This research has produced eco-friendly paver blocks by removing cement and replacing it with plastic waste, which will benefit the environment, save money, reduce carbon dioxide emissions, and be suitable for low-traffic areas, all of which contribute to sustainable development.

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  • 13.
    Inqiad, Waleed Bin
    et al.
    Military College of Engineering (MCE), National University of Science and Technology (NUST), Islamabad 44000, Pakistan.
    Siddique, Muhammad Shahid
    Military College of Engineering (MCE), National University of Science and Technology (NUST), Islamabad 44000, Pakistan.
    Alarifi, Saad S.
    Department of Geology and Geophysics, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
    Butt, Muhammad Jamal
    COMSATS University Islamabad, Abbottabad Campus, Pakistan.
    Najeh, Taoufik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Gamil, Yaser
    Department of Civil Engineering, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia.
    Comparative analysis of various machine learning algorithms to predict 28-day compressive strength of Self-compacting concrete2023Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 9, nr 11, artikel-id e22036Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Construction industry is indirectly the largest source of CO2 emissions in the atmosphere, due to the use of cement in concrete. These emissions can be reduced by using industrial waste materials in place of cement. Self-Compacting Concrete (SCC) is a promising material to enhance the use of industrial wastes in concrete. However, there are very few methods available for accurate prediction of its strength, therefore, reliable models for estimating 28-day Compressive Strength (C–S) of SCC are developed in current study by using three Machine Learning (ML) algorithms including Multi Expression Programming (MEP), Extreme Gradient Boosting (XGB), and Random Forest (RF). The ML models were meticulously developed using a dataset of 231 points collected from internationally published literature considering seven most influential parameters including cement content, quantities of fly ash and silica fume, water content, coarse aggregate, fine aggregate, and superplasticizer dosage to predict C–S. The developed models were evaluated using different statistical errors including Root Mean Square Error (RMSE), Mean Absolute Error (MAE), coefficient of determination (R2) etc. The results showed that the XGB model outperformed the MEP and RF model in terms of accuracy with a correlation R2 = 0.998 compared to 0.923 for MEP and 0.986 for RF. Similar trend was observed for other error metrices. Thus, XGB is the most accurate model for estimating C–S of SCC. However, it is pertinent to mention here that it does not give its output in the form of an empirical equation like MEP model. The construction of these empirical models will help to efficiently estimate C–S of SCC for practical purposes.

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  • 14.
    Jingili, Nuru
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Oyelere, Solomon Sunday
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Malmström Berghem, Simon
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Brännström, Robert
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Laine, Teemu H.
    Department of Digital Media, Ajou University, Suwon, 16499, South Korea.
    Balogun, Oluwafemi Samson
    School of Computing, University of Eastern Finland, Kuopio, Finland.
    Adolescents’ perceptions of active school transport in northern Sweden2023Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 9, nr 10, artikel-id e20779Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Active school transport (AST) refers to using active means of transport such as walking, cycling, or riding a non-motorised scooter to school. It can help improve adolescents’ physical activity levels and create a more sustainable environment. The study involved 70 adolescents (45 boys and 25 girls) aged 13 to 14 from one school in Skellefteå, in Northern Sweden. In an online questionnaire, they were asked about their perceptions of cycling, walking, and riding a non-motorised scooter to school. This study used descriptive statistics, multiple regression analysis, and hypothesis testing with ANOVA to analyse the collected data and compare the perceptions of different types of transport on safety, environmental, and personal factors among adolescents in Northern Sweden. According to the results, more adolescents walked to school than cycled, and significantly few rode a non-motorised scooter to school. Most adolescents believe walking or cycling to school is a great way to exercise. Furthermore, the study also revealed that many adolescents avoid using AST due to the time it takes. Although the study showed that adolescents felt sufficient support for using AST from schools and parents, the number of adolescents using motorised transport is higher during winter than in summer. Additionally, most of them were more confident about cycling and walking to school than riding a non-motorised scooter and thought using AST was nice. Finally, most adolescents perceived having complete control over their transport options when going to school. The research indicates that it is crucial to implement interventions that inspire children to be interested and excited about using AST. These strategies should include fostering an AST culture that is fun and positive, as well as creating environments that are safe and supportive. The research results will guide the creation of a persuasive game that can motivate adolescents to use AST and measure its effectiveness.

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  • 15.
    Khan, Majid
    et al.
    COMSATS University Islamabad, Abbottabad Campus, 22060, Pakistan.
    Khan, Adil
    Department of Civil and Structural Engineering, University of Bradford, Bradford, West Yorkshire, BD7 1DP, UK.
    Khan, Asad Ullah
    Department of Civil Engineering, University of Engineering and Technology, Peshawar, 25120, Pakistan.
    Shakeel, Muhammad
    Department of Civil Engineering, University of Engineering and Technology, Peshawar, 25120, Pakistan.
    Khan, Khalid
    Department of Civil Engineering, University of Engineering and Technology, Peshawar, 25120, Pakistan.
    Alabduljabbar, Hisham
    Department of Civil Engineering, College of Engineering in Al-Kharj, Prince Sattam Bin Abdulaziz University, Al-Kharj 11942, Saudi Arabia.
    Najeh, Taoufik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Gamil, Yaser
    Department of Civil Engineering, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia.
    Intelligent prediction modeling for flexural capacity of FRP-strengthened reinforced concrete beams using machine learning algorithms2023Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 10, artikel-id e23375Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fiber-reinforced polymers (FRP) are widely utilized to improve the efficiency and durability of concrete structures, either through external bonding or internal reinforcement. However, the response of FRP-strengthened reinforced concrete (RC) members, both in field applications and experimental settings, often deviates from the estimation based on existing code provisions. This discrepancy can be attributed to the limitations of code provisions in fully capturing the nature of FRP-strengthened RC members. Accordingly, machine learning methods, including gene expression programming (GEP) and multi-expression programming (MEP), were utilized in this study to predict the flexural capacity of the FRP-strengthened RC beam. To develop data-driven estimation models, an extensive collection of experimental data on FRP-strengthened RC beams was compiled from the experimental studies. For the assessment of the accuracy of developed models, various statistical indicators were utilized. The machine learning (ML) based models were compared with empirical and conventional linear regression models to substantiate their superiority, providing evidence of enhanced performance. The GEP model demonstrated outstanding predictive performance with a correlation coefficient (R) of 0.98 for both the training and validation phases, accompanied by minimal mean absolute errors (MAE) of 4.08 and 5.39, respectively. In contrast, the MEP model achieved a slightly lower accuracy, with an R of 0.96 in both the training and validation phases. Moreover, the ML-based models exhibited notably superior performances compared to the empirical models. Hence, the ML-based models presented in this study demonstrated promising prospects for practical implementation in engineering applications. Moreover, the SHapley Additive exPlanation (SHAP) method was used to interpret the feature's importance and influence on the flexural capacity. It was observed that beam width, section effective depth, and the tensile longitudinal bars reinforcement ratio significantly contribute to the prediction of the flexural capacity of the FRP-strengthened reinforced concrete beam.

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  • 16.
    Khan, Yasar
    et al.
    Department of Structural Engineering, Military College of Engineering (MCE), National University of Science and Technology (NUST), Islamabad 44000, Pakistan.
    Zafar, Adeel
    Department of Structural Engineering, Military College of Engineering (MCE), National University of Science and Technology (NUST), Islamabad 44000, Pakistan.
    Rehman, Muhammad Faisal
    University of Engineering and Technology Peshawar, Abbottabad campus, Abbottabad, 22060, Pakistan.
    Javed, Muhammad Faisal
    Department of Civil Engineering, COMSATS University Islamabad, Abbottabad Campus, Abbottabad, 22060, Pakistan.
    Iftikhar, Bawar
    Department of Civil Engineering, COMSATS University Islamabad, Abbottabad Campus, Abbottabad, 22060, Pakistan.
    Gamil, Yaser
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. Department of Civil Engineering, School of Engineering, Monash University Malaysia, Jalan Lagoon Selatan, 47500 Bandar Sunway, Selangor, Malaysia.
    Bio-inspired based meta-heuristic approach for predicting the strength of fiber-reinforced based strain hardening cementitious composites2023Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 9, nr 11, artikel-id e21601Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A recently introduced bendable concrete having hundred times greater strain capacity provides promising results in repair of engineering structures, known as strain hardening cementitious composites (SHHCs). The current research creates new empirical prediction models to assess the mechanical properties of strain-hardening cementitious composites (SHCCs) i.e., compressive strength (CS), first crack tensile stress (TS), and first crack flexural stress (FS), using gene expression programming (GEP). Wide-ranging records were considered with twelve variables i.e., cement percentage by weight (C%), fine aggregate percentage by weight (Fagg%), fly-ash percentage by weight (FA%), Water-to-binder ratio (W/B), super-plasticizer percentage by weight (SP%), fiber amount percentage by weight (Fib%), length to diameter ratio (L/D), fiber tensile strength (FTS), fiber elastic modulus (FEM), environment temperature (ET), and curing time (CT). The performance of the models was deduced using correlation coefficient (R) and slope of regression line. The established models were also assessed using relative root mean square error (RRMSE), Mean absolute error (MAE), Root squared error (RSE), root mean square error (RMSE), objective function (OBF), performance index (PI) and Nash-Sutcliffe efficiency (NSE). The resulting mathematical GP-based equations are easy to understand and are consistent disclosing the originality of GEP model with R in the testing phase equals to 0.8623, 0.9269, and 0.8645 for CS, TS and FS respectively. The PI and OBF are both less than 0.2 and are in line with the literature, showing that the models are free from overfitting. Consequently, all proposed models have high generalization with less error measures. The sensitivity analysis showed that C%, Fagg%, and ET are the most significant variables for all three models developed with sensitiveness index higher than 10 %. The result of the research can assist researchers, practitioners, and designers to assess SHCC and will lead to sustainable, faster, and safer construction from environment-friendly waste management point of view.

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  • 17.
    Nilsson, Jens
    et al.
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Samhällsvetenskap.
    Lundmark, Carina
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Samhällsvetenskap.
    The effect of personal values and the roles on representational principles in natural resource management decision-making2020Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 6, nr 5, artikel-id e04032Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The aim of this article is to explore how personal values and the role of the representative influence representation principles when making decisions in natural resource management. This was tested in an empirical case of wildlife management in Sweden, the regional Wildlife Conservation Committees (WCCs). These WCCs consist of a mix of actors in collaborative settings, where both politicians and interest organization representatives make decisions on wildlife related issues. The results show that the value dimension of self-enhancement, associated with giving importance to values such as achievement and power, significantly affects a representational style associated with following the representative's personal preferences when making decisions, the trustee principle. The role of the representative also significantly affects representational style when making decisions in these cases, where the interest organizational representatives more often follow the party principle, i.e., the view of the parties or organization they represent, than the political actors. Age also had a significant impact where older representatives relied more on the trustee principle than their younger peers. The implications of these results are that personal values in this case matters for decision-making, which is in line with earlier research on decision-making on environmental issues. Further, politicians behave atypically for the Swedish context relying more on the trustee principle rather than the party principle, which policy makers should take into consideration when designing collaborative arenas similar to the WCCs.

  • 18.
    Priyashantha, Hasitha
    et al.
    Department of Molecular Sciences, Swedish University of Agricultural Sciences, Box 7015, SE-750 07, Uppsala, Sweden.
    Hansson, Lars
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Träteknik. Department of Ocean Operations and Civil Engineering, Faculty of Engineering, Norwegian University of Science and Technology, 6025, Alesund, Norway.
    Forsman, Peter
    Norrmejerier, Mejerivagen 2, SE-906 22, Umeå, Sweden.
    Lundh, Åse
    Department of Molecular Sciences, Swedish University of Agricultural Sciences, Box 7015, SE-750 07, Uppsala, Sweden.
    Hetta, Mårten
    Department of Applied Animal Science and Welfare, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden.
    Computed tomography (CT) scanning to visualize eye formation and internal structure in Grevé cheese2024Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 10, nr 13, artikel-id e33408Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The size and distribution of the eyes play a crucial role for the sensory attributes, aesthetic value and quality of the cheese. This article focuses on investigating the feasibility of using computed tomography (CT) scanning as a non-destructive tool to observe early-stage eye formation in Grevé cheese within an industrial trial. It is crucial to achieve a perfect combination of small and big sized eyes, evenly distributed within the cheese wheel, without having cracks/splits for optimal quality. Such variations could be visualized using CT-scanning of cheeses at a young and mature stage by providing high-resolution, three-dimensional CT-scanning images of the cheese&apos;s internal structure, without the need for physical dissection. Further, the distribution of eyes, their shape and number, could be visualized and compared for the same cheese scanned at young and mature stages. Thus, the importance of monitoring eye formation through non-destructive techniques is emphasized to ensure consistent product quality.

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  • 19.
    Saibi, Hakim
    et al.
    Geology Department, College of Science, UAEU, Al-Ain, United Arab Emirates.
    Khosravi, Sadieh
    Geology Department, College of Science, UAEU, Al-Ain, United Arab Emirates.
    Cherkose, Biruk Abera
    Geology Department, College of Science, UAEU, Al-Ain, United Arab Emirates.
    Smirnov, Maxim
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Kebede, Yosef
    Geological Survey of Ethiopia, Ethiopia.
    Fowler, Abdel-Rahman
    Geology Department, College of Science, UAEU, Al-Ain, United Arab Emirates.
    Magnetotelluric data analysis using 2D inversion: A case study from Al-Mubazzarah Geothermal Area (AMGA), Al-Ain, United Arab Emirates2021Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 7, nr 6, artikel-id e07440Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Geothermal manifestations (hot springs) emerge in the Al-Mubazzarah Geothermal Area (AMGA), Al-Ain city, Abu Dhabi Emirate, United Arab Emirates. This paper presents the application and results of a Magnetotelluric (MT) survey, which was carried out in 2017 at the AMGA geothermal field. The MT method was used to investigate the variations in the electrical conductivity beneath the AMGA. This study focuses on characterizing the patterns of subsurface electrical conductivity of the AMGA geothermal reservoir. Dimensionality analysis of the measured MT data indicate that 2D inversion is appropriate for the subsurface resistivity interpretation. The inversion results support a model consisting of three resistivity-defined layers; from top to bottom they are: (1) a shallow layer with resistivity ranging from 10 to 20 Ωm, representing recent alluvial and windblown deposits, (2) a second conductive layer with resistivities less than 10 Ωm, beneath the first layer. This layer is recognized as the Tertiary carbonate sequence in the region, (3) a deep, moderate to relatively high resistive zone, 10–30 Ωm beginning at 800 m depth and reaching 4 km depth in the northern part of the profile, representing Mesozoic basement rocks. The observed moderate to high resistivity zone (10–30 Ωm) in the 2D model may represent a region where the hot groundwaters originated (geothermal reservoir), with the hottest geothermal located at a depth greater than 4 km. The geothermal reservoir zone is also represented by a low to high density contrast and a low to moderate magnetic susceptibility, as indicated in the inverted potential field data models, and confirmed the existence of a north dipping major fault.

  • 20.
    Saroughi, Mohsen
    et al.
    Department of Irrigation and Reclamation Engineering, Faculty of Agricultural Engineering and Technology, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran.
    Mirzania, Ehsan
    Department of Water Engineering, University of Tabriz, Tabriz, Iran.
    Achite, Mohammed
    Faculty of Nature and Life Sciences, Laboratory of Water and Environment, Hassiba Benbouali University of Chlef, Chlef, 02180, Algeria.
    Katipoğlu, Okan Mert
    Department of Civil Engineering, Erzincan Binali Yıldırım University, Erzincan, Turkey.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Vishwakarma, Dinesh Kumar
    Department of Irrigation and Drainage Engineering, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Udham Singh Nagar, Uttarakhand, 263145, India.
    Chung, Il-Moon
    Department of Water Resources and River Research, Korea Institute of Civil Engineering and Building Technology, Goyang-si, 10223, Republic of Korea.
    Alreshidi, Maha Awjan
    Department of Chemistry, University of Ha'il, Ha'il, 81441, Saudi Arabia.
    Yadav, Krishna Kumar
    Faculty of Science and Technology, Madhyanchal Professional University, Ratibad, Bhopal, 462044, India; Environmental and Atmospheric Sciences Research Group, Scientific Research Center, Al-Ayen University, Thi-Qar, Nasiriyah 64001, Iraq.
    Evaluate effect of 126 pre-processing methods on various artificial intelligence models accuracy versus normal mode to predict groundwater level (case study: Hamedan-Bahar Plain, Iran)2024Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 10, nr 7, artikel-id e29006Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The estimation of groundwater levels is crucial and an important step in ensuring sustainable management of water resources. In this paper, selected piezometers of the Hamedan-Bahar plain located in west of Iran. The main objective of this study is to compare effect of various pre-processing methods on input data for different artificial intelligence (AI) models to predict groundwater levels (GWLs). The observed GWL, evaporation, precipitation, and temperature were used as input variables in the AI algorithms. Firstly, 126 method of data pre-processing was done by python programming which are classified into three classes: 1- statistical methods, 2- wavelet transform methods and 3- decomposition methods; later, various pre-processed data used by four types of widely used AI models with different kernels, which includes: Support Vector Machine (SVR), Artificial Neural Network (ANN), Long-Short Term memory (LSTM), and Pelican Optimization Algorithm (POA) - Artificial Neural Network (POA-ANN) are classified into three classes: 1- machine learning (SVR and ANN), 2- deep learning (LSTM) and 3- hybrid-ML (POA-ANN) models, to predict groundwater levels (GWLs). Akaike Information Criterion (AIC) were used to evaluate and validate the predictive accuracy of algorithms. According to the results, based on summation (train and test phases) of AIC value of 1778 models, average of AIC values for ML, DL, hybrid-ML classes, was decreased to −25.3%, −29.6% and −57.8%, respectively. Therefore, the results showed that all data pre-processing methods do not lead to improvement of prediction accuracy, and they should be selected very carefully by trial and error. In conclusion, wavelet-ANN model with daubechies 13 and 25 neurons (db13_ANN_25) is the best model to predict GWL that has −204.9 value for AIC which has grown by 5.23% (−194.7) compared to the state without any pre-processing method (ANN_Relu_25).

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  • 21.
    Sewar, Yousef
    et al.
    Civil Engineering Department, Faculty of Engineering, Thamar University, 9676, Thamar, Yemen.
    Amran, Mugahed
    Department of Civil Engineering, College of Engineering, Prince Sattam Bin Abdulaziz University, 11942 Alkharj, Saudi Arabia; Department of Civil Engineering, Faculty of Engineering and IT, Amran University, 9677 Amran, Yemen.
    Avudaiappan, Siva
    Departamento de Ciencias de la Construccion, Facultad de Ciencias de la Construccion y Ordenamiento Territorial Universidad Tecnologica Metropolitana, Santiago, Chile.
    Gamil, Yaser
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och brand. Department of Civil Eng., School of Eng., Monash University Malaysia, Jalan Lagoon Selatan, 47500 Sunway, Selangor, Malaysia.
    Rashid, Raizal S.M.
    Department of Civil Engineering, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
    Bonding strength performance of bamboo-based composite materials: An in-depth insight for sustainable construction applications2024Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 10, nr 13, artikel-id e32155Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    This review systematically examines the multitude of factors influencing bonding strength in bamboo-based composite materials, given the rising prominence of bamboo as a green building material. With bamboo&apos;s inherent variability in mechanical properties and structure, engineered bamboo products have emerged to address challenges related to connections and joints. Such advancements have necessitated a detailed exploration of adhesive systems, a significant cost determinant in bamboo production. The adhesive bonding mechanism in bamboo, akin to wood, involves intricate processes including adhesive spreading, penetration, and solidification, influenced by the unique chemical composition of bamboo. The interfacial bond quality plays a pivotal role in determining the durability and performance of the final products, with numerous factors such as bamboo species, layered structure, adhesive type, and treatment types impacting the mechanical properties. Particular attention is given to the disparities in physical and mechanical properties between the bamboo culm&apos;s core and shell layers, attributing complexities to the gluing process. Examining shear failure strength reveals its criticality in mechanical investigations, with variations in bonding strength affecting the outcome. The review underscores the need for consistent quality control and adept manipulation of these influential factors for the successful manufacture of bamboo-based products. A comprehensive discussion ensues on the variables controlling the bonding properties of the developed bamboo products, aiming to evaluate and highlight the optimal parameters and procedures essential for enhancing the quality and reliability of bamboo-based composite materials for sustainable construction applications.

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  • 22.
    Shezad, Nasir
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    D'Agostini, Marco
    Department of Industrial Engineering, University of Padova, Via Marzolo, 9, Padova, 35131, Italy.
    Ezzine, Ali
    Department of Industrial Engineering, University of Padova, Via Marzolo, 9, Padova, 35131, Italy.
    Franchin, Giorgia
    Department of Industrial Engineering, University of Padova, Via Marzolo, 9, Padova, 35131, Italy.
    Colombo, Paolo
    Department of Industrial Engineering, University of Padova, Via Marzolo, 9, Padova, 35131, Italy; Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, USA.
    Akhtar, Farid
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    3D-printed zeolite 13X-Strontium chloride units as ammonia carriers2023Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 9, nr 9, artikel-id e19376Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The selective catalytic reduction (SCR) system in automobiles using urea solution as a source of NH3 suffers from solid deposit problems in pipelines and poor efficiency during engine startup. Although direct use of high pressure NH3 is restricted due to safety concerns, which can be overcome by using solid sorbents as NH3 carrier. Strontium chloride (SrCl2) is considered the best sorbent due to its high sorption capacity; however, challenges are associated with the processing of stable engineering structures due to extraordinary volume expansion during the NH3 sorption. This study reports the fabrication of a novel structure consisting of a zeolite cage enclosing the SrCl2 pellet (SPZC) through extrusion-based 3D printing (Direct Ink Writing). The printed SPZC structure demonstrated steady sorption of NH3 for 10 consecutive cycles without significant uptake capacity and structural integrity loss. Furthermore, the structure exhibited improved sorption and desorption kinetics than pure SrCl2. The synergistic effect of zeolite as physisorbent and SrCl2 as chemisorbent in the novel composite structure enabled the low-pressure (<0.4 bar) and high-pressure (>0.4 bar) NH3 sorption, compared to pure SrCl2, which absorbed NH3 at pressures above 0.4 bar. Regeneration of SPZC composite sorbent under evacuation showed that 87.5% percent of NH3 was desorbed at 20 °C. Thus, the results demonstrate that the rationally designed novel SPZC structure offers safe and efficient storage of NH3 in the SCR system and other applications.

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  • 23.
    Sissakian, Varoujan K.
    et al.
    Department of Petroleum Engineering, Komar University of Science and Technology, Sulaymaniyah, KRG, Iraq.
    Gahfur, Ala A.
    Department of Geology, University of Regina, Canada.
    Al-Ansari, Nadhir
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geoteknologi.
    Omer, Hassan O.
    Deventer, the Netherlands.
    Abdulhaq, Hawkar A.
    Szeged University, Hungary.
    Structural and geomorphological study of Bradost, Chinara, Shireen and Sare Musa anticlines, Iraqi Kurdistan Region2023Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 9, nr 7, artikel-id e18375Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Bradost and Chinara mountains are two well-known geomorphic features in the Iraqi Kurdistan Region (IKR), forming two anticlines, besides Shireen and Sare Musa anticlines, which are located north of the Bradost anticline, all four anticlines trend NW – SE. The four anticlines are dissected by the Greater Zab River that swings along its course within the anticlines due to tens of very old landslides and/or plunges. The four studied anticlines are dissected by different thrust faults, which extend for a few kilometers. The thrust faults trend NW – SE; however, locally they deflect from the main trend. The Lower Jurassic rocks are the oldest exposed rocks in the studied area, whereas the rocks of the Bekhme Formation form the carapace of the Bradost and Chinara anticlines. Different structural and geomorphological features were interpreted from satellite images and those which are accessible were checked in the field, all of them indicate the four anticlines exhibit lateral growth. We have measured different aspects to elucidate the type of folds. The four anticlines are Detachment folds, with shallow decollement, which ranges in depth between (100–250) m.

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  • 24.
    Velarde, Lisbania
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap. Department of Chemistry, Faculty of Science and Technology, Universidad Mayor de San Simón, UMSS, Cochabamba, Bolivia.
    Nikjoo, Dariush
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Escalera, Edwin
    Department of Chemistry, Faculty of Science and Technology, Universidad Mayor de San Simón, UMSS, Cochabamba, Bolivia.
    Akhtar, Farid
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Bolivian natural zeolite as a low-cost adsorbent for the adsorption of cadmium: Isotherms and kinetics2024Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 10, nr 1, artikel-id e24006Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Population growth in recent years has led to increased wastewater production and pollution of water resources. This situation also heavily affects Bolivia, so wastewater treatment methods and materials suitable for Bolivian society should be explored. This study investigated the natural Bolivian Zeolite (BZ) and its NaCl-modified structure (NaBZ) as adsorbents for cadmium removal from water. The natural BZ and the modified form NaBZ were investigated by different physicochemical characterization techniques. Furthermore, XPS and FT-IR techniques were used to investigate the adsorption mechanisms. The cadmium adsorption on BZ and NaBZ was analyzed using various mathematical models, and the Langmuir model provided a better description of the experimental adsorption data with cadmium adsorption capacities of 20.2 and 25.6 mg/g for BZ and NaBZ, respectively. The adsorption followed the pseudo-second order kinetics. The effect of different parameters, such as initial cadmium concentration and pH on the adsorption was studied. In addition, the results of the regeneration test indicated that both BZ and NaBZ can be regenerated by using hydrochloric acid (HCl). Finally, the adsorption experiment of BZ and NaBZ on a real water sample (brine from Salar de Uyuni salt flat) containing a mixture of different heavy metals was carried out. The results obtained in this study demonstrate the effectiveness of natural BZ and modified NaBZ in the removal of heavy metals from wastewater.

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  • 25.
    Venkatesh S, Naveen
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Drift, underhåll och akustik.
    Sripada, Divya
    Centre for Advanced Data Science, Vellore Institute of Technology, Chennai, India.
    V, Sugumaran
    School of Mechanical Engineering (SMEC), Vellore Institute of Technology, Chennai, India.
    Aghaei, Mohammadreza
    Department of Ocean Operations and Civil Engineering, Norwegian University of Science and Technology (NTNU), 6009, Ålesund, Norway; Department of Sustainable Systems Engineering (INATECH), University of Freiburg, 79110, Freiburg, Germany.
    Detection of visual faults in photovoltaic modules using a stacking ensemble approach2024Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 10, nr 6, artikel-id e27894Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Faults in photovoltaic (PV) modules may occur due to various environmental and physical factors. To prevent faults and minimize investment losses, fault diagnosis is crucial to ensure uninterrupted power production, extended operational lifespan, and a high level of safety in PV modules. Recent advancements in inspection techniques and instrumentation have significantly reduced the cost and time required for inspections. A novel stacking-based ensemble approach was performed in the present study for the accurate classification of PV module visible faults. The present study utilizes AlexNet (a pre-trained network) to extract image features from the aerial images of PV modules with the aid of MATLAB software. Furthermore, J48 algorithm was applied to perform the feature selection task to determine the most relevant features. The features derived as output from the J48 algorithm were passed onto train eight base classifiers namely, Naïve Bayes, logistic regression (LR), J48, random forest (RF), multilayer perceptron (MLP), logistic model tree (LMT), support vector machines (SVM) and k-nearest neighbors (kNN). The best performing five classifiers on the front run with higher classification accuracies were selected to formulate three categories of stacking ensemble groups as follows: (i) three-class ensemble (SVM, kNN, and LMT), (ii) four-class ensemble (SVM, kNN, LMT, and RF), and (iii) five-class ensemble (SVM, kNN, LMT, RF, and MLP). A comparison in the performance of the aforementioned stacked ensembles was evaluated with different meta classifiers. The obtained results infer that the four-class stacking ensemble model (SVM, kNN, LMT, and RF) with RF as the predictor achieved the highest possible classification accuracy of 99.04%.

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  • 26.
    Volpp, Joerg
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Produkt- och produktionsutveckling.
    Laser light absorption of high-temperature metal surfaces2023Ingår i: Heliyon, E-ISSN 2405-8440, Vol. 9, nr 10, artikel-id e21021Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Laser beam absorption is the basic effect to enable many high-temperature applications and processes. However, high temperature absorption data of metals is often not available or based on theoretical assumptions. In this work, using a newly developed experimental arrangement to measure laser light absorption on liquid metal surfaces even above boiling temperature enabled the derivation of absorption values in those regimes. Results indicate that interband absorption must be considered even at such high temperatures against common theoretical predictions. It is shown that the simulated nearly constant absorption depth and absorption values between melting and boiling temperatures indicate that the increased atom distance due to thermal expansion, denoting a reduced absorption volume, is counterbalanced by the increased statistical availability of conduction electrons due to Fermi band broadening.

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