Search Results (28)

The COVID-19 pandemic intensified labor shortages and safety challenges in Jordan’s construction sector, revealing systemic vulnerabilities in its reliance on migrant workers. This study evaluates an advanced robotic bricklaying system through simulation of 10 residential buildings (80 units) under Jordanian building codes (JSBC 2020) and strict pandemic constraints, including workforce absenteeism rates of 30% based on ILO data and Ministry of Health density protocols. The simulation-based analysis, which focuses specifically on standardized housing designs, demonstrates 84% faster bricklaying (6.75 vs. 43.2 days/unit), 94% productivity retention during absenteeism, 15% mortar waste reduction (advancing SDG 9), and 60% lower transmission risk versus manual methods. Despite higher rental costs (15,168 JD vs. 12,946 JD/unit), accelerated construction timelines substantially reduced overhead expenses, yielding a rapid <5-month payback period. Policy recommendations target vocational training programs and financial subsidies for small contractors, aligning with Jordan’s Economic Modernization Vision (2022–2024). Limitations involve architectural irregularities and supply chain dependencies; future work requires field validation to complement these simulation findings. Full article

This study examines housing affordability trends in Central Europe, focusing on the Czech Republic, Slovakia, Austria, and Poland, in the wake of recent global disruptions including the COVID-19 pandemic, the 2021–2022 energy crisis, and the war in Ukraine. These events have intensified housing affordability challenges by driving up property prices, rental costs, and energy expenses. Using data from December 2022 to March 2023, the paper analyzes wage levels relative to housing costs in major cities—Prague, Brno, Bratislava, Vienna, Graz, Warsaw, and Kraków—through price-to-income and rent-to-income ratios. The findings reveal that affordability is most strained in Czech cities, particularly Prague, where property prices outpace wages, while Vienna demonstrates better affordability due to higher average incomes. The study integrates real estate platform data with official statistics and employs spatial mapping and exploratory econometric testing to identify affordability patterns and disparities. It concludes that affordability outcomes are shaped by wage dynamics, housing supply constraints, migration pressures, and policy responses. The study underscores the importance of targeted housing policies and wage interventions to address these challenges and highlights the need for cross-country policy learning and regional coordination to improve housing affordability and market resilience across Central Europe. Full article

Enhancing farmers’ behaviors toward cultivated land quality protection is a crucial support in achieving sustainable agricultural development and the national food security strategy. This study aims to investigate the impact of land transfer-in on farmers’ behaviors regarding cultivated land quality protection, explore the underlying mechanisms, and analyze group heterogeneity. To achieve this, the study empirically estimates the impact of land transfer-in on farmers’ behaviors in protecting cultivated land quality using micro-survey data from 743 households in Hubei Province, while addressing endogeneity and conducting robustness checks. The study further explores the mechanisms and heterogeneity of the effects of land transfer-in on farmers’ cultivated land quality protection behaviors. The results reveal that (1) land transfer-in significantly increases the likelihood of farmers taking actual actions to protect cultivated land quality and enhances their awareness, thereby promoting protective behaviors; (2) land transfer-in facilitates these protective behaviors mainly through income incentives and social network interactions, while rental constraints may have a suppressive effect; (3) full-time farmers, those with higher agricultural literacy, those who access agricultural knowledge online, and those affected by natural disasters are more likely to engage in proactive land quality protection behaviors after land transfer-in. Full article

Efficient supply–demand management in Product-as-a-Service (PaaS) markets requires tools to evaluate pricing strategies while integrating sustainability goals like reuse, efficiency, and carbon footprint reduction. This paper introduces a declarative modeling framework aimed at balancing the three pillars of profitability, cost optimization, and sustainability in PaaS markets. The framework addresses risks such as equipment failure, usage variability, and economic fluctuations, helping providers optimize pricing and operating costs while enabling customers to manage expenses. A declarative model is developed to assess the PaaS market balance to determine optimal leasing offers and requests for quotations. A case study is used to validate the framework, involving devices with specific rental prices and failure rates, as well as customer expectations and budget constraints. Computational experiments demonstrate the model’s practical applicability in real-world scenarios and it can be used by PaaS providers to develop competitive leasing strategies, policymakers to assess market stability, and enterprises to optimize procurement decisions. The findings show that the framework can guide decision making, offering insights into the impact of new technologies, compatibility conditions for leasing offers, and strategies for balancing providers’ profits and customers’ costs. The proposed framework has broad applicability across industries such as manufacturing, healthcare, logistics, and IT infrastructure leasing, where efficient resource allocation and lifecycle management are crucial. Full article

Governments are encouraging public transportation and bicycle-sharing systems to promote sustainable development and reduce greenhouse gas emissions. Despite the expansion of Taipei’s YouBike program, many stations frequently run out of bikes or docking spaces, and current redistribution strategies are suboptimal. This study proposes a novel approach to optimize YouBike allocation under resource constraints. We first used K-means clustering to group stations with similar rental profiles, reducing the number of models needed. A random forest model selected key crowd grid factors as input variables for a long short-term memory (LSTM) prediction model to accurately predict demand patterns, including during special events or weather changes. A genetic algorithm then determined optimal station configurations and provided return station recommendations, considering user destinations and station dock ratios, while minimizing manual redistribution. Simulations demonstrated that the proposed system meets user needs, enhances operational efficiency, and significantly reduces manual redistribution costs. Our methods have practical applicability for YouBike managers, indicating that user compliance with recommendations can offset the need for manual redistribution and support the current policy of recommending stations within 600 m of the user’s destination. Full article

The increasing trend of farmers abandoning their farmland amid urbanization poses significant challenges to sustainable agricultural development and threatens national food security. This study employs evolutionary game theory to analyze the drivers, constraints, and policy regulation strategies associated with the farmland abandonment by farmers in the context of urbanization and aging in China. The findings indicate that urbanization and demographic aging significantly influence farmers’ decisions to abandon their farmland. Government regulations, including incentives and penalties, face constraints from various factors. Farmers are often drawn to abandon their land because of the higher income potential from urban employment and land rental, coupled with the burden of farming and opportunity costs. Conversely, potential losses from land transfer income, agricultural product revenues, the quality of farmland, and lower levels of aging serve as constraints that affect farmers’ decision-making and land utilization behaviors. Furthermore, proactive regulation by local governments can effectively deter farmers from abandoning their land. However, the success of government policies in protecting farmland relies on a synergistic approach that balances incentives and regulations. Therefore, it is crucial for policymakers to consider multiple factors and adapt policy designs flexibly to align with local conditions. This study aims to provide theoretical insights and practical guidance for developing more effective and scientifically grounded farmland protection policies. Full article

This study investigates the perceived ease of recycling in Glendale, Salt Lake City, Utah, USA, by household size, age, income, and gender. While existing research has broadly explored how sociodemographic factors impact recycling, there is a lack of comprehensive studies analyzing these factors within specific local contexts. This study aims to identify specific barriers and motivators across different demographics to enhance local recycling efforts using Glendale as a case study. Data were collected through an online survey of 111 respondents and analyzed using both quantitative and qualitative methods. The survey included questions about the demographic information, perceptions of recycling ease, and barriers to recycling. The analysis revealed that one-person households and young adults (18–35) face constraints such as limited space for recyclables, a lack of access to recycling bins in rental units, or high costs. Older adults (56 years or older) are highly committed but may face physical challenges. Higher-income households report higher participation due to better access and awareness, whereas lower-income households encounter significant barriers such as limited facility access and insufficient information. Gender differences indicate that women are slightly more proactive and committed to recycling compared to men. Recommendations include expanding recycling facilities, targeted educational campaigns, and economic incentives to encourage lower-income households, males, younger, and older adults. Addressing these demographic-specific barriers can improve recycling rates and contribute to more sustainable communities. Future studies should include in-person surveys as one of the limitations of this study is that an online survey format may introduce biases and the exclusion of residents without internet access. Full article

Guaranteeing efficient evacuations in urban communities is critical for preserving lives, minimizing disaster impacts, and promoting community resilience. Challenges such as high population density, limited evacuation routes, and communication breakdowns complicate evacuation efforts. Vulnerable populations, urban infrastructure constraints, and the increasing frequency of disasters further contribute to the complexity. Despite these challenges, the importance of timely evacuations lies in safeguarding human safety, enabling rapid disaster response, preserving critical infrastructure, and reducing economic losses. Overcoming these hurdles necessitates comprehensive planning, investment in resilient infrastructure, effective communication strategies, and continuous community engagement to foster preparedness and enhance evacuation efficiency. This research looks into the complexities of evacuation dynamics within urban residential areas, placing a particular focus on the interaction between joint-rental arrangements and family ties and their influence on evacuation strategies during emergency situations. Using agent-based modeling, evacuation simulation scenarios are implemented using the Changhongfang community (Shanghai) while systematically exploring how diverse interpersonal relationships impact the efficiency of evacuation processes. The adopted methodology encompasses a series of group experiments designed to determine the optimal proportions of joint-rental occupants within the community. Furthermore, the research examines the impact of various exit selection strategies on evacuation efficiency. Simulation outcomes shed light on the fundamental role of interpersonal factors in shaping the outcomes of emergency evacuations. Additionally, this study emphasizes the critical importance of strategic exit selections, revealing their potential to significantly enhance overall evacuation efficiency in urban settings. Full article

Surveys on the optimum seismic design of structures reveal that many investigations focus on minimizing initial costs while satisfying performance constraints. Although reducing initial costs while complying with earthquake design codes significantly ensures occupant safety, it may still cause considerable economic losses and fatalities. Therefore, calculating potential earthquake damages over the structure’s lifetime is essential from an optimal Life-Cycle Cost (LCC) design perspective. LCC analysis evaluates economic feasibility, including construction, operation, occupancy, maintenance, and end-of-life costs. The population-based, meta-heuristic Ideal Gas Molecular Movement (IGMM) algorithm has proven effective in solving highly nonlinear mono- and multi-objective engineering problems. This paper investigates the LCC-based mono- and multi-objective optimum design of a 3D four-story concrete building structure using the Endurance Time (ET) method, which is employed for its efficiency in estimating structural responses under varying seismic hazard levels. The novelty of this work lies in integrating the ET method with the IGMM algorithm to comprehensively address both economic and performance criteria in seismic design. The results indicate that the proposed technique significantly reduces minor injury costs, rental costs, and income costs by 22%, 16%, and 16%, respectively, achieving a total reduction of 10% in all structural Life-Cycle Costs, which is considered significant. Full article

Mobile cranes represent conventional construction machinery that is indispensable for the erection of most prefabricated buildings, especially those containing heavy components. However, it is also common knowledge that the engagement of these machines has a significant influence on the environment, various social aspects of the construction process, and its economic benefits. Optimal positioning of the mobile crane on the construction site, primarily driven by the contractor’s interest to perform assembly operations with expensive machinery as effectively as possible, considerably reduces not only the costs of engaging such a machine but indirectly also its negative impacts on construction sustainability. This paper discusses an exact nonlinear model for the optimization task. The optimization model consists of a cost objective function that is subject to various duration and positioning constraints for the mobile crane, including bounds on its degrees of freedom of movement and stop positions. Because the model formulation includes discontinuous and non-smooth expressions, nonlinear programming with discontinuous derivatives (DNLP) was employed to ensure the optimal solution was reached. The model provides the mobile crane operator with exact key information that enables the complete and optimal assembly of the building structure under consideration. Additionally, the information gained on the optimal distribution of the mobile crane rental period to assembly operations allows for a detailed duration analysis of the entire process of building structure erection, which can be used for its further improvement. An application example is given in this study to demonstrate the advantages of the proposed approach. Full article

A study of two warehouse inventory systems with a production unit is developed in this article with some constraints which are of practical applicability to optimize the total production cycle and its cost. A production unit evolves in three different states to retain its quality and prolong its lifetime: the state of producing items, the state of reworking the identified defective items, and the state of being idle. It processes the items up to a certain time point. The screening process starts immediately after a product comes out of the production unit. The classified non-defective items are first stored in own warehouse ($OW$), after filling to its maximum capacity, and the remaining items fill in the first block $\left({RW}_1\right)$ of the rental warehouse $\left(RW\right)$. All identified defective items are stored in the second block $\left({RW}_2\right)$ of $RW$. The holding cost of an item is higher in $RW$ than $OW$. All defective items are sent to the production unit for re-do processes as a single lot immediately after the stop of the production and re-do items are stored in ${RW}_1$ to satisfy the demand. The items in the ${RW}_1$ are of higher priority in satisfying the demands after the stop of the production unit in producing new items as to deduce the total cost. Demand is assumed as both time and advertisement dependent and is encouraged once production starts. The deterioration rate differs in both warehouses. No backlog is entertained. The study is directed to achieve optimum total cycle cost towards the attainment of the optimum production time slot and the entire cycle of the system. We have arrived at explicit expressions for the total cost function of the entire production cycle. An analytic optimization process of the discriminant method is employed in the form of an algorithm to arrive at the optimum total cost. It provides a numerical illustration of a specific environment. The implications of the current research work are as follows. The optimum utility of production units in three different states in arriving at the optimum total cost is extensively studied with respect to deterioration, demand, and production rates. It also examined the influence of fluctuating deterioration, demand, and production parameters in arriving at optimum deterioration cost, holding cost, and total cycle cost, as they have important managerial insights. The effect of rental charges on the optimum total cost is examined as the system is used for multi-purpose storage. Full article

We carried out a search of over 12,000 houses offered on the rental market in Catalonia and assessed the possibility of families below the poverty threshold being able to rent these homes. In this regard, we wanted to evaluate whether the economic situation of families is able to influence their social environment, surroundings, and safety. We observed how their economic situation can allow families the possibility of developing a life without exposure to health risks, and how economic constraints result in disadvantages in several areas of life. The results show how families at risk of poverty live in less favourable conditions and experience a widening of different gaps, with current prices leading to a possible poverty trap for the most disadvantaged groups. The higher the percentage of the population below the threshold, the lower the possibility of not being able to rent a house compared to areas with a lower prevalence of population below the threshold. This association was observed both when considering the risk linearly and non-linearly. Linearly, the probability of not renting a house was reduced by 8.36% for each 1% increase in the prevalence of population at risk of extreme poverty. In the second, third and fourth percentage quartiles, the probability of not being able to rent a house decreased by 21.13%, 48.61%, and 57.79%, respectively. In addition, the effect was different inside and outside of metropolitan areas, with the former showing a decrease of 19.05% in the probability of renting a house, whereas outside metropolitan areas the probability increased by 5.70%. Full article

Housing costs, including rent, have become a significant economic burden for millions of floating population families in urban China, affecting their living standards and influencing migration decision-making. Using data from the China Migrants Dynamic Survey (CMDS) in 2012 and 2017, this study analyzes the spatial patterns of rent, family income, and the rent-to-income ratio among different regions, cities, and groups. Results show that rent and the rent-to-income ratio have an inverse correlation with the regional economy, with lower ratios observed in eastern coastal areas compared to the central and western regions, especially the northeast. High-level cities record higher incomes, higher rents, and higher rent-to-income ratios, and groups with higher educational levels and occupational characteristics exhibit higher affordability. Rent plays a role in the flow and changes of the floating population, and the housing burden has become a key constraint for long-term residence or migration. Developed provinces and municipalities in the eastern region and high-level cities remain major destinations for migrants, but rising house prices impede permanent settlement through commercial house purchases. The government should consider migrants’ demands for housing and increase the supply of subsidized housing, such as public rental housing, for the floating population. Full article

With the advent and development of Industry 4.0 and 5.0, manufacturing modes have changed and numerous newly complicated and integrated village-level industrial parks have emerged in the Southeast of China, where several enterprises are gathered in the same multistory building. The number of floors and surrounding enterprises can have an impact on accident risk. To reduce the overall risk level of industrial parks, the layout of enterprises with different risks needs to be well designed and optimized. However, to date, limited studies have been conducted to emphatically consider safety and optimize the enterprise layout at an industrial area level, and most studies focus on the cost of the layout. Therefore, this study proposed three biobjective mathematical optimization models to obtain the trade-off between minimizing risk and maximizing rental profit. Risk factors include the enterprise location and the association risk; the enterprise inherent safety risks are not considered. To solve this problem, a specific linearization strategy was proposed and an epsilon-constraint method was applied to obtain Pareto-optimal solutions. Subsequently, an industrial park in Shunde, China, was considered as a case study to verify the performance of the proposed models and methods. Finally, a sensitivity analysis of critical parameters was conducted. The critical factors influencing the objective functions were also analyzed to provide valuable managerial insights. Full article

The study aims to estimate different land leasing entities’ intentions and drivers to grow non-grain crops. In 2021, following a multistage sampling technique based on non-grain farmland, 264 farmers from the Zengcheng District of China were interviewed using a well-structured questionnaire based on the theory of planned behavior and transaction cost. The structural equation model was used to quantitatively reveal the influence mechanism of the non-grain use of the transferred farmland. The difference in the non-grain use of the transferred farmland was analyzed from the perspective of the differentiation of the renting entities. The results showed that the profit margin of non-grain and food crops, and the follow-up behavior of business entities, all promote the non-grain utilization of transferred farmland; however, the transaction costs of non-grain utilization and the endowment constraints of agricultural businesses inhibit the non-grain utilization of farmland. The non-grain crops in the suburbs are more profitable, and the transaction costs of the farmland leasing entities are low, so they tend to be grain-free; the rents of the farmland in the outer suburbs are low and can be operated on a large scale, and the leasing entities tend to be grain-oriented. Large-scale leasing entities tend to grow grain, while small-scale leasing entities tend to grow non-grain crops. In general, large-scale leasing entities in the outer suburbs have high transaction costs and low land rents and tend to be grain-oriented. The small-scale leasing entities in the suburbs are close to the market, the transaction costs are low, the rental price of farmland is high, and they are more inclined to grow non-grain crops. The non-grain utilization of the leased farmland should be treated separately, the supervision of the grain production capacity of the leased farmland should be carried out, and the rotation of grain and non-grain crops should be encouraged; the moderate scale operation in outer suburbs should be encouraged, and the construction of high-standard basic farmland for grain-growing farmland should be promoted. Full article