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The framework of this paper is financial mathematics and, more specifically, the control of data fraud and manipulation with their subsequent economic effects, namely, in financial markets. The purpose of this paper is to calculate the global loss or gain, which supposes, for the borrower, a change of the interest rate while the contracted loan is in force or, in another case, the loan has finished.

The methodology used in this work has been, in the first place, a review of the existing literature on the topic of manipulability and abusiveness of the loan interest rates applied by banks; in the second place, the introduction of a mathematical-financial analysis to calculate the interests paid in excess; and, finally, the compilation of several sentences issued on the application of the so-called mortgage loan reference index (MLRI) to mortgage loans in Spain.

There are three main contributions in this paper. First, the calculation of the interests paid in excess in the amortization of mortgage loans referenced to an overvalued interest rate. Second, an empirical application shows the amount to be refunded to a Spanish consumer when amortizing his/her mortgage loan referenced to the MLRI instead of the Euro InterBank Offered Rate (EURIBOR). Third, consideration has been made to the effects and the possible solutions to the legal problems arising from this type of contract.

This research is a useful tool capable of implementing the financial calculation needed to find out overpaid interests in mortgage loans and to execute the sentences dealing with this topic. However, a limitation of this study is the lack of enough sentences on mortgage loans referenced to the MLRI to get some additional information about the number of borrowers affected by these legal sentences and the amount refunded by the financial institutions.

To the best of the authors’ knowledge, this is the first time that deviations in the payment of interests have been calculated when amortizing a mortgage.

The construction industry has long been criticized for unethical conduct. The owner usually manages the contractor's opportunistic behaviors by employing a professional supervisor, but there is a risk of covert collusion between the supervisor and contractor. Based on the principal–agent theory and collusion theory, this paper aims to investigate optimal collusion-proof incentive contracts.

This paper presents a game-theoretic framework comprising an owner, supervisor and contractor, who interact and pursue maximized self-profits. Built upon the fixed-price incentive contract, cost-reimbursement contract, and revenue-sharing contract, different collusion-proof incentive contracts are investigated. A real project case is used to validate the developed model and derived results.

This paper shows that the presence of unethical collusion undermines the owner's interests. Especially, the possibility of agent collusion may induce the owner to abandon extracting quality information from the supervisor. Furthermore, information asymmetry significantly affects the construction contract selection, and the application conditions for different incentive contracts are provided.

This study still has some limitations that deserve further exploration. First, this study explores contractor–supervisor collusion but ignores the possibility of the supervisor abusing authority to extort the contractor. Second, to focus on collusion, this paper ignores the supervision costs. What's the optimal supervision effort that the owner should induce the supervisor to exert? Finally, this paper assumes that the colluders involved always keep their promises. However, what if the colluders may break their promises?

Several collusion-proof incentive contracts are explored in a project management setting. The proposed incentive contracts can provide the project owner with effective and practical tools to inhibit covert collusion in construction management and thus safeguard construction project quality.

This study expands the organization collusion theory to the field of construction management and investigates the optimal collusion-proof incentive contracts. In addition, this study is the first to investigate the effects of information asymmetry on contract selection.

The author studies forms over finite fields obtained as the determinant of Hermitian matrices and use these determinatal forms to define and study the base polynomial of a square matrix over a finite field.

The authors give full proofs for the new results, quoting previous works by other authors in the proofs. In the introduction, the authors quoted related references.

The authors get a few theorems, mainly describing some monic polynomial arising as a base polynomial of a square matrix.

As far as the author knows, all the results are new, and the approach is also new.

This paper aims to study the joint decision making of advance selling and service cancelation for service provides with limited capacity when consumers are overconfident.

For the case in which consumers encounter uncertainties about product valuation and consumption states in the advance period and are overconfident about the probability of a good state, we study how the service provider chooses the optimal sales strategy among the non-advance selling strategy, the advance selling and disallowing cancelation strategy, and the advance selling and allowing cancelation strategy. We also discuss how overconfidence influences the service provider’s decision making.

The results show that when service capacity is sufficient, the service provider should adopt advance selling and disallow cancelation; when service capacity is insufficient, the service provider should still implement advance selling but allow cancelation; and when service capacity is extremely insufficient, the service provider should offer spot sales. Moreover, overconfidence weakens the necessity to allow cancelation under sufficient service capacity and enhances it under insufficient service capacity but is always advantageous to advance selling.

The obtained results provide managerial insights for service providers to make advance selling decisions.

This paper is among the first to explore the effect of consumers’ overconfidence on the joint decision of advance selling and service cancelation under capacity constraints.

In China, information-based construction management (ICM) has not obtained the expected results because of the benefit game between construction enterprises and the government. Promoting ICM is a long-term, complex and dynamic game process. Therefore, an evolutionary game model is established to promote ICM.

MATLAB was used to conduct evolutionary game analysis on the behavioural strategies of two parties. System stability analysis and numerical simulation were conducted. The variables affecting ICM realization were analysed and comprehensively considered. The optimal stability strategy and key variables were obtained.

The results show that the system includes four evolutionarily stable strategies (ESSs) with 10 decisive parameters. Information technology costs, benefits, reputation, the government intervention level, the enterprise ICM level and the degree of reward and punishment determine the ideal ESS. Increasing tangible benefits, enhancing corporate reputation, improving the level of government guidance and reducing intervention costs can promote ICM implementation. Rewards are more effective than punishments, and appropriate rewards should be determined.

First, reducing labour disputes, accidents and environmental pollution brings great social and ecological benefits; hence, the recognition of external benefits and the establishment of a benefit compensation mechanism by the government will be a future focus of research (Jia et al., 2020). Second, this study considered only the government and construction enterprises, and there may be other stakeholders, such as owners and the public, in the ICM adoption process, which needs further analysis (Zhang and Li, 2022). Third, this research is based on the specific context of government intervention in ICM. The selection of parameters and the determination of values were based on the national conditions in China. Therefore, the generalizability of the research results to other countries and other political contexts needs to be further improved (Hardie et al., 2013; Martínez-Román et al., 2017). Fourth, the empirical data were collected from Shandong Province and a pilot project, and the universality of the data remains to be verified. Nevertheless, the data were used only for the initial values of the simulation, which did not affect the simulation path.

(1) This study comprehensively summarized the benefit and cost indexes for the government and enterprises to promote ICM and constructed the payment matrix model. (2) This study determined the theoretical relation that the parameters should meet when system evolves into a certain strategy, and the research findings provide recommendations for overall control for the government and enterprises to synergistically adopt the ICM. (3) The study determined the influence of the main parameters on system evolution path and identified the core parameters, thus providing targeted improvement recommendations for the government and enterprises.

Real-time data-based management can ensure product quality and production safety and improve decision-making and efficiency. For the government, ICM can effectively reduce project quality and safety accidents, labour disputes, supplier mix-ups and environmental pollution, thus reducing the government's management costs and improving social benefits.

(1) Based on the challenges of ICM implementation, the payment matrix is constructed, with the cost and benefit parameters fully considered. (2) This study determines the theoretical relationship that should be met when both parties coordinate their implementation and when enterprises implement independently, and the optimal strategy is specified. (3) Incorporating an actual case, a simulation is conducted to clarify the influence of a single parameter on the evolutionary path of behaviours. (4) A decision-making basis for governments and enterprises to control and improve ICM is provided.

The purpose of this study is to investigate the Dynamics of micropolar – water B Fluids flow simultaneously under the influence of thermal radiation and Soret–Dufour Mechanisms.

The thermal radiation contribution, the chemical change and heat generation take fluidity into account. The flow equations are used to produce a series of dimensionless equations with appropriate nondimensional quantities. By using the spectral homotopy analysis method (SHAM), simplified dimensionless equations have been quantitatively solved. With Chebyshev pseudospectral technique, SHAM integrates the approach of the well-known method of homotopical analysis to the set of altered equations. In terms of velocity, concentration and temperature profiles, the impacts of Prandtl number, chemical reaction and thermal radiation are studied. All findings are visually shown and all physical values are calculated and tabulated.

The results indicate that an increase in the variable viscosity leads to speed and temperature increases. Based on the transport nature of micropolar Walters B fluids, the thermal conductivity has great impact on the Prandtl number and decrease the velocity and temperature. The current research was very well supported by prior literature works. The results in this paper are anticipated to be helpful for biotechnology, food processing and boiling. It is used primarily in refrigerating systems, tensile heating to large-scale heating and oil pipeline reduction.

All results are presented graphically and all physical quantities are computed and tabulated.

The purpose of this study is to explore numerical scrutinization of micropolar and Walters-B non-Newtonian fluids motion under the influence of thermal radiation and chemical reaction.

The two fluids micropolar and Walters-B liquid are considered to start flowing from the slot to the stretching sheet. A magnetic field of constant strength is imposed on their flow transversely. The problems on heat and mass transport are set up with thermal, chemical reaction, heat generation, etc. to form partial differential equations. These equations were simplified into a dimensionless form and solved using spectral homotopy analysis method (SHAM). SHAM uses the basic concept of both Chebyshev pseudospectral method and homotopy analysis method to obtain numerical computations of the problem.

The outcomes for encountered flow parameters for temperature, velocity and concentration are presented with the aid of figures. It is observed that both the velocity and angular velocity of micropolar and Walters-B and thermal boundary layers increase with increase in the thermal radiation parameter. The decrease in velocity and decrease in angular velocity occurred are a result of increase in chemical reaction. It is hoped that the present study will enhance the understanding of boundary layer flow of micropolar and Walters-B non-Newtonian fluid under the influences of thermal radiation, thermal conductivity and chemical reaction as applied in various engineering processes.

All results are presented graphically and all physical quantities are computed and tabulated.

The purpose of this study is to examine how formal and informal institutions play a role in the Iranian context in shaping corporate social responsibility (CSR) policies and practices.

Using a multiple case-study approach combining comparative and cross-sectional methods with semi-structured interviews, primary data was collected from eight corporations that actively participated in CSR activities in Iran. A microanalysis approach was used to examine the meanings and dynamics in the data. Through thematic analysis and pattern-matching techniques, the authors separately examined the roles of formal and informal institutions. Cross-case analysis was used to highlight the cases’ similarities and differences.

This study demonstrates that both formal and informal institutional structures exist in Iran and that both types influence CSR. This study also shows that informal institutions (such as personal values, culture, religion, traditions, charity and philanthropy) play a more explicit role than formal institutions (such as legal regulations and laws) in shaping CSR adoption policies and practices. The results indicate that, among institutions linked to CSR, formal and informal institutions are complementary and potentiate each other in Iran. Nevertheless, compared to formal ones, informal institutions play a more prominent role in shaping CSR policies and practices.

The authors recognize that, although the eight corporations are large, and although they interviewed their key personnel, they do not claim that these findings are generalizable, owing to the qualitative nature of the study and the small number of selected corporations.

This study makes relevant theoretical and empirical contributions. First, it contributes to the growing body of CSR literature that highlights the necessity of linking informal and formal institutions. Although the CSR literature lacks research on informal institutions in developing economies, researchers have yet to push forward and explore how the CSR adoption process works in developing economies that have influential informal institutions.

The paper aims to propose an innovative two-stage decision model to address the sustainable-resilient supplier selection and order allocation (SSOA) problem in the single-valued neutrosophic (SVN) environment.

First, the sustainable and resilient performances of suppliers are evaluated by the proposed integrated SVN-base-criterion method (BCM)-an acronym in Portuguese of interactive and multi-criteria decision-making (TODIM) method, with consideration of the uncertainty in the decision-making process. Then, a novel multi-objective optimization model is formulated, and the best sustainable-resilient order allocation solution is found using the U-NSGA-III algorithm and TOPSIS method. Finally, based on a real-life case in the automotive manufacturing industry, experiments are conducted to demonstrate the application of the proposed two-stage decision model.

The paper provides an effective decision tool for the SSOA process in an uncertain environment. The proposed SVN-BCM-TODIM approach can effectively handle the uncertainties from the decision-maker’s confidence degree and incomplete decision information and evaluate suppliers’ performance in different dimensions while avoiding the compensatory effect between criteria. Moreover, the proposed order allocation model proposes an original way to improve sustainable-resilient procurement values.

The paper provides a supplier selection process that can effectively integrate sustainability and resilience evaluation in an uncertain environment and develops a sustainable-resilient procurement optimization model.

Forests are negatively affected from rapid world population increase and industrialization that create intense pressures on natural resources and the possibility of an achieving circular economy. Forests can be considered as essential resources for providing sustainable society and meeting the requirements of future generations and circular economy. Therefore sustainable production tools as part of circular economy can be handled as one of the basic indicators for achieving circular economy. Accordingly the main purpose of this study is developing a novel rough – fuzzy multi-criteria decision-making model (MCDM) for evaluation sustainable production for forestry firms in Eastern Black Sea Region.

For determining 18 criteria weights a novel Rough PIPRECIA (PIvot Pairwise RElative Criteria Importance Assessment) method is developed. Eight decision-makers (DMs) participated in the research, and to obtain group rough decision matrix, rough Dombi weighted geometric averaging (RNDWGA) operator has been applied. For evaluation forestry firms fuzzy MARCOS (Measurement of alternatives and ranking according to COmpromise solution) method was utilized.

After application developed model the fourth alternative was found as the best. Sensitivity analysis and comparison were made to present the applicability of this method.

Development of novel integrated Rough PIPRECIA-Fuzzy MARCOS model with emphasis on developing new Rough PIPRECIA method.