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This paper examines the dynamics of structural transformation in Morocco since 1970 by analyzing input-output tables expressed in terms of employment and output levels across 24 sectors.

This study employs a twofold methodological approach. Firstly, it examines the evolution of sectoral employment shares over time using World Bank data. Secondly, it utilizes Input-Output analysis to examine structural shifts in Morocco's economy, focusing on sector-specific output and employment data. The primary data source is the Eora Global Supply Chain Database, covering the years 1970, 1980, 1990, 2000, and 2015. Additionally, to transition from production-based to employment-based input-output tables, the study leverages employment and output data from the Penn World Tables to calculate the diagonal labor coefficient matrix.

First, our analysis reveals that Morocco's economic transformation has been slower compared to high-income countries. Structural changes, as evidenced by the evolution of employment shares by sector, show a gradual decline in agricultural employment share over the period 1991-2019, accompanied by a shift towards the services sector. This shift, driven by favorable conditions in the services sector and increased capital use in agriculture, has resulted in premature deindustrialization. The industrial sector's employment share has remained stable due to its capital-intensive nature. Second, Input-Output analysis reveals a pronounced premature tertiarization of the Moroccan economy. Between 1990 and 2000, the tertiary sector saw a dramatic rise in both backward (167%) and forward (68%) linkages, while the primary sector's backward linkages fell by 33% during the same period. Although the primary sector’s linkages increased by 10% from 2000 to 2015, the secondary sector experienced a consistent decline in backward linkages, dropping 12% from 1990 to 2000 and an additional 10% from 2000 to 2015. Employment linkage analysis further underscores this shift, with a 12% increase in the tertiary sector’s backward linkages from 1990 to 2000, contrasted by significant declines in the primary (51%) and secondary (7%) sectors. These trends highlight an unsustainable move towards services without concurrent industrial development, challenging balanced economic development.

As it is unanimous, the structural transformation of Morocco remains relatively slow and characterized by a shift of the labor factor from the primary sector to the tertiary sector, with a limited job creation by the secondary sector considered as the pillar of any structural transformation. This paper advances the field of research on structural transformation by elucidating the premature tertiarization of the Moroccan economy and the slowness pace at which the transformation of its economic fabric is occurring, thereby filling the empirical gap.

The purpose of this study is to further investigate the potential benefits brought about by the development of modern technology in the steel construction industry. Specifically, the study focuses on the optimization of tapered members for pre-engineered steel structures, aligning with Eurocode 3 standards. By emphasizing the effectiveness of material utilization in construction, this research aims to enhance the structural performance and safety of buildings. Moreover, it recognizes the pivotal role played by such advancements in promoting economic growth through the reduction of material waste, optimization of cost-efficiency and support for sustainable construction practices.

Structural performance at initial analysis and final analysis of the selected critical frame were carried out using Dlubal RSTAB 8.18. The structural frame stability and sway imperfections were checked based on MS EN1993-1-1:2005 (EC3). To assess the structural stability of the portal frame using MS EN 1993-1-1:2005 (EC3), cross-sectional resistance and member buckling resistance were verified based on Clause 6.2.4 – Compression, Clause 6.2.5 – Bending Moment, Clause 6.2.6 – Shear, Clause 6.2.8 – Bending and Shear, Clause 6.2.9 – Bending and Axial Force and Clause 6.3.4 – General Method for Lateral and Lateral Torsional Buckling of Structural Components.

In this study, the cross sections of the web-tapered rafter and column were classified under Class 4. These involved the consideration of elastic shear resistance and effective area on the critical steel sections. The application of the General Method on the verification of the resistance to lateral and lateral torsional buckling for structural components required the extraction of some parameters using structural analysis software. From the results, there was only 5.90% of mass difference compared with the previous case study.

By classifying the web-tapered cross sections of the rafter and column under Class 4, the study accounts for important factors such as elastic shear resistance and effective area on critical steel sections.

The paper aims to analyze the structural integrity of an existing offshore platform located in the Northern Adriatic Sea, followed by the topside decommissioning and the re-utilization of the jacket as a wind turbine support. The structural integrity assessment against the in-place and the long-term actions is accomplished by using a reduced basis finite element method (RB-FEA) software program assessing the capability of the jacket to be used as a support for wind turbines at the end of its life cycle as oil and gas (O&G) platform.

The project starts by modeling the jacket, and subsequently, the structural analyses for the in-place loads in operative and extreme conditions are performed. Then, the fatigue analysis is carried out in order to define the cumulative damage necessary to evaluate the possibility to use the jacket as a wind turbine support.

The results show that the jacket, at the end of the service life as O&G platform, is able to withstand the loads produced by the installation of the wind turbine since the analyses are satisfied even with the conservative approach used which overestimates the thickness loss assuming a linear increasing value during the service life.

Because of the chosen approach, the study presents some limitations, especially concerning the real state of the platform which has been defined considering the thickness loss only. Additionally, a 1D model was used to perform the analyses, and hence, a 3D model could help in evaluating the critical points with higher precision.

The assessment of the structure could be improved by modeling a digital twin of the asset allowing a real-time monitoring which, however, involves a huge amount of data to be processed, so a suitable simulation technology must be used.

The RB-FEA proposed by Akselos is suitable to perform the analyses speeding up the processing of the data even in real time.

The paper's goal is to examine and illustrate the useful uses of submodeling in finite element modeling for topology optimization and stress analysis. The goal of the study is to demonstrate how submodeling – more especially, a 1D approach – can reliably and effectively produce ideal solutions for challenging structural issues. The paper aims to demonstrate the usefulness of submodeling in obtaining converged solutions for stress analysis and optimized geometry for improved fatigue life by studying a cantilever beam case and using beam formulations. In order to guarantee the precision and dependability of the optimization process, the developed approach will also be validated through experimental testing, such as 3-point bending tests and 3D printing. Using 3D finite element models, the 1D submodeling approach is further validated in the final step, showing a strong correlation with experimental data for deflection calculations.

The authors conducted a literature review to understand the existing research on submodeling and its practical applications in finite element modeling. They selected a cantilever beam case as a test subject to demonstrate stress analysis and topology optimization through submodeling. They developed a 1D submodeling approach to streamline the optimization process and ensure result validity. The authors utilized beam formulations to optimize and validate the outcomes of the submodeling approach. They 3D-printed the optimized models and subjected them to a 3-point bending test to confirm the accuracy of the developed approach. They employed 3D finite element models for submodeling to validate the 1D approach, focusing on specific finite elements for deflection calculations and analyzed the results to demonstrate a strong correlation between the theoretical models and experimental data, showcasing the effectiveness of the submodeling methodology in achieving optimal solutions efficiently and accurately.

The findings of the paper are as follows: 1. The use of submodeling, specifically a 1D submodeling approach, proved to be effective in achieving optimal solutions more efficiently and accurately in finite element modeling. 2. The study conducted on a cantilever beam case demonstrated successful stress analysis and topology optimization through submodeling, resulting in optimized geometry for enhanced fatigue life. 3. Beam formulations were utilized to optimize and validate the outcomes of the submodeling approach, leading to the successful 3D printing and testing of the optimized models through a 3-point bending test. 4. Experimental results confirmed the accuracy and validity of the developed submodeling approach in streamlining the optimization process. 5. The use of 3D finite element models for submodeling further validated the 1D approach, with specific finite elements showing a strong correlation with experimental data in deflection calculations. Overall, the findings highlight the effectiveness of submodeling techniques in achieving optimal solutions and validating results in finite element modeling, stress analysis and optimization processes.

The originality and value of the paper lie in its innovative approach to utilizing submodeling techniques in finite element modeling for structural analysis and optimization. By focusing on the reduction of finite element models and the creation of smaller, more manageable models through submodeling, the paper offers designers a more efficient and accurate way to achieve optimal solutions for complex problems. The study's use of a cantilever beam case to demonstrate stress analysis and topology optimization showcases the practical applications of submodeling in real-world scenarios. The development of a 1D submodeling approach, along with the utilization of beam formulations and 3D printing for experimental validation, adds a novel dimension to the research. Furthermore, the paper's integration of 1D and 3D submodeling techniques for deflection calculations and validation highlights the thoroughness and rigor of the study. The strong correlation between the finite element models and experimental data underscores the reliability and accuracy of the developed approach. Overall, the originality and value of this paper lie in its comprehensive exploration of submodeling techniques, its practical applications in structural analysis and optimization and its successful validation through experimental testing.

Mega construction projects (MCPs), which play an important role in the economy, society and environment of a country, have developed rapidly in recent years. However, due to frequent social conflicts caused by the negative social impact of MCPs, social risk control has become a major challenge. Exploring the relationship between social risk factors and social risk from the perspective of risk evolution and identifying key factors contribute to social risk control; but few studies have paid enough attention to this. Therefore, this study aims to systematically analyze the impact of social risk factors on social risk based on a social risk evolution path.

This study proposed a social risk evolution path for MCPs explaining how social risk occurs and develops with the impact of social risk factors. To further analyze the impact quantitatively, a social risk analysis model combining structural equation model (SEM) with Bayesian network (BN) was developed. SEM was used to verify the relationship in the social risk evolution path. BN was applied to identify key social risk factors and predict the probabilities of social risk, quantitatively. The feasibility of the proposed model was verified by the case of water conservancy projects.

The results show that negative impact on residents’ living standards, public opinion advantage and emergency management ability were key social risk factors through sensitivity analysis. Then, scenario analysis simulated the risk probability results with the impact of different states of these key factors to obtain management strategies.

This study creatively proposes a social risk evolution path describing the dynamic interaction of the social risk and first applies the hybrid SEM–BN method in the social risk analysis for MCPs to explore effective risk control strategies. This study can facilitate the understanding of social risk from the perspective of risk evolution and provide decision-making support for the government coping with social risk in the implementation of MCPs.

Formwork design and construction for reinforced concrete buildings take significant time, effort and money. Construction procedures are time-consuming for designers and costly for the contractor. Poor engineering decisions have led to several workplace accidents in the construction industry. This paper aims to present an integrated building information modeling – genetic algorithm (BIM-GA) model to automate formwork design, 3D visualization and optimization.

Data are precisely extracted from a 3D structural model and used to optimize formwork design based on available formwork components and prices. Optimization models are made using GA approach. A library of 3D formwork components was modeled and stored using Revit. The optimized design solution thereafter would be visualized automatically in Revit to readily acquire formwork quantities schedules and shop drawings.

A case study illustrating the proposed approach demonstrated that using BIM will reduce formwork design, quantification and drawing time by more than 50% of the traditional approach with safer design and accurate results due to process automation and optimize cost for the given data.

This research introduces an innovative integrated BIM and GA model for the optimization and automation of slab formwork design, which has significantly benefited the construction industry. The utilization of GA in the optimization process allows for the attainment of an optimal formwork design, ultimately leading to a reduction in construction cost and time.

This study aims to analyze the relationship between the consequences of the pandemic and the housing sector with econometric tests that allow for structural breaks.

Study data were collected weekly between March 9, 2020, and February 4, 2022, and analyzed for Turkey. In the model of the study, housing loans were used as a housing market indicator, and the number of new deaths and new cases were used as data related to the pandemic. The exchange rate, which affects the use of housing loans, was added to the model as a control variable. This study was analyzed to examine the relationship between the pandemic and the housing sector, time series analysis techniques that allow structural breaks were used.

Based on the result of the analyses, it was concluded that there is a long-run relationship between the pandemic stages and housing markets along with structural breaks. As a result of the time-varying causality test developed to determine the causality relationship between the variables and its direction, a bidirectional causality relationship was identified between all variables at certain dates.

Study data were collected weekly between March 9, 2020, and February 4, 2022, and analyzed in the case of Turkey.

Based on results of the study, it is recommended that policy makers and market actors take into account extraordinary situations such as pandemics and create a budget allocation that is always ready to use for this purpose.

The empirical examination of the relationship between the pandemic and the housing sector in Turkey provides originality to this study in terms of its topic, sample, methodology, contribution to the literature and potential policy recommendations.

The present study examines the relational, structural and cognitive dimensions of social capital developed within members of self-help groups (SHGs) in India.

The study has used multistage random sampling to collect 1,285 samples covering 4 districts such as Sundargarh, Mayurbhanj, Koraput and Rayagada in Odisha. Structure equation modeling (SEM) is used in hypothesis formulation and data analysis.

The result highlighted that relational, structural and cognitive social capital are significant to social capital formation among the participants of SHGs. However, structural social capital has the highest impact compared with others in building social capital.

Policy professionals, development agencies and government departments must use social capital as a catalyzing agent for the successful implementation of welfare schemes in rural areas.

The paper adds valuable contributions in advancing the theory of social capital. Additionally, marginalized households fail to uplift their socioeconomic conditions in developing nations due to a lack of social capital; hence, its measurement is critical.

The peer-review history for this article is available at: https://publons.com/publon/10.1108/IJSE-10-2023-0804.

Considering the construction industry’s vital role in economic development and social consequences, this study seeks to pinpoint critical barriers hindering Turkey’s sustainable construction (SC). Although several studies highlighted the barriers to SC worldwide, none identified the critical factors. By identifying and understanding these barriers, the research aims to comprehensively understand practices and formulate strategic recommendations to promote sustainable construction.

A systematic approach is adopted to achieve the research objectives. The study involves identifying potential barriers to SC with a systematic literature review. A questionnaire was organized and distributed via e-mail to architects, civil engineers, and contractors. The criticality of identified barriers was determined with normalized mean value analysis, and critical barrier factors (CBFs) to SC were isolated with exploratory factor analysis. Finally, the effect size of these factors was quantified through structural equation modeling.

This study identified 32 critical barriers hindering the SC in the Turkish construction industry among 49 barriers. Furthermore, this study revealed six CBFs to SC that are “inadequate supervision and control of SC,” “fear of transition to sustainable construction and disruptions in adoption,” “lack of educational opportunities,” “return on investment and financial bias,” “awareness and knowledge gap about SC,” and “lack of demand from stakeholders.” Among them, “awareness and knowledge gap about SC,” “fear of transition to SC,” “lack of educational opportunities,” “lack of demand from stakeholders,” and “inadequate supervision and control of SC” were determined as the very highly crucial CBFs hindering SC.

Although some studies have identified the barriers to SC qualitatively and quantitatively, studies have yet to provide insights into the critical barrier factors hindering SC. Therefore, this study comprehensively and quantitatively determines the relevant CBFs to SC using exploratory factor analysis and utilizes confirmatory factor analysis and structural equation modeling to present a structural model of how critical factors affect the SC.

Aiming at the inefficiency of solving the Sobol index using the traditional mathematical analytical method, a Sobol global sensitivity analysis method is proposed.

In this paper, a support vector regression (SVR) surrogate model is constructed to solve the Sobol index. The optimal combination of SVR hyperparameters is obtained by using the improved beluga whale optimization (IBWO). Meanwhile, in order to solve the problem that Sobol sequences will form correlation regions in high-dimensional space leading to the uneven distribution of sampling points, a scrambled strategy is introduced in the Sobol sensitivity analysis using IBWO-SVR. Thus, the IBWO-SVR-SS sensitivity analysis model is established.

The results of two test functions show that the method further improves the accuracy of the sensitivity analysis. Finally, the first-order Sobol index and second-order Sobol index are solved by the IBWO-SVR-SS method using the metro bogie frame as an engineering example. Through the analysis results, the key design parameters of the frame and the design parameter combinations with more obvious coupling relationships are identified, providing a strong reference for the subsequent analysis and structural optimization.

Sobol sensitivity analysis using the surrogate model method can effectively improve the efficiency of the solution. In addition, IBWO is used for the optimization of the SVR hyperparameters to improve the accuracy and efficiency of the optimization, and finally, the correction of the Sobol sequence through the introduction of the disruption strategy also further improves the accuracy of the sensitivity analysis of Sobol.