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The paper proposed a fast procedure for solving the reliability-based robust design optimization (RBRDO) by modifying the RBRDO formulation and transforming it into a series of RBRDO subproblems. Then for each subproblem, the objective function, constraint function and reliability index are approximated using Taylor series expansion, and their approximate forms depend on the deterministic design vector rather than the random vector and the uncertain estimation in the inner loop of RBRDO can be avoided. In this way, it can greatly reduce the evaluation number of performance function. Lastly, the trust region method is used to manage the above sequential RBRDO subproblems for convergence.

As is known, RBRDO is nested optimization, where the outer loop updates the design vector and the inner loop estimate the uncertainties. When solving the RBRDO, a large evaluation number of performance functions are needed. Aiming at this issue, the paper proposed a fast integrated procedure for solving the RBRDO by reducing the evaluation number for the performance functions. First, it transforms the original RBRDO problem into a series of RBRDO subproblems. In each subproblem, the objective function, constraint function and reliability index caused are approximated using simple explicit functions that solely depend on the deterministic design vector rather than the random vector. In this way, the need for extensive sampling simulation in the inner loop is greatly reduced. As a result, the evaluation number for performance functions is significantly reduced, leading to a substantial reduction in computation cost. The trust region method is then employed to handle the sequential RBRDO subproblems, ensuring convergence to the optimal solutions. Finally, the engineering test and the application are presented to illustrate the effectiveness and efficiency of the proposed methods.

The paper proposes a fast procedure of solving the RBRDO can greatly reduce the evaluation number of performance function within the RBRDO and the computation cost can be saved greatly, which makes it suitable for engineering applications.

The standard deviation of the original objective function of the RBRDO is replaced by the mean and the reliability index of the original objective function, which are further approximated by using Taylor series expansion and their approximate forms depend on the deterministic design vector rather than the random vector. Moreover, the constraint functions are also approximated by using Taylor series expansion. In this way, the uncertainty estimation of the performance functions (i.e. the mean of the objective function, the constraint functions) and the reliability index of the objective function are avoided within the inner loop of the RBRDO.

Surrogate models are extensively used to substitute real models which are expensive to evaluate in the time-dependent reliability analysis. Normally, different surrogate models have different scopes of application. However, information is often insufficient for analysts to select the most appropriate surrogate model for a specific application. Thus, the result precited by individual surrogate model tends to be suboptimal or even inaccurate. Ensemble model can effectively deal with the above concern. This work aims to study the application of ensemble model for reliability analysis of time-independent problems.

In this work, a method of reliability analysis for time-dependent problems based on ensemble learning of surrogate models is developed. The ensemble of surrogate models includes Kriging, radial basis function, and support vector machine. The prediction is approximated by the weighted average model. The ensemble learning of surrogate models is updated by finding and adding the sample points with large prediction errors throughout the entire procedure.

The effectiveness of the proposed method is verified by several examples. The results show that the ensemble of surrogate models can effectively propagate the uncertainty of time-varying problems, and evaluate the reliability with high prediction accuracy and computational efficiency.

This work proposes an adaptive learning framework for the uncertainty propagation of time-dependent problems based on the ensemble of surrogate models. Compared with individual surrogate models, the ensemble model not only saves the effort of selecting an appropriate surrogate model especially when the knowledge of unknown problem is lacking, but also improves the prediction accuracy and computational efficiency.

This study aims to derive a novel spatial numerical method based on multidimensional local Taylor series representations for solving high-order advection-diffusion (AD) equations.

The parabolic AD equations are reduced to the nonhomogeneous elliptic system of partial differential equations by utilizing the Chebyshev spectral collocation method (ChSCM) in the temporal variable. The implicit-explicit local differential transform method (IELDTM) is constructed over two- and three-dimensional meshes using continuity equations of the neighbor representations with either explicit or implicit forms in related directions. The IELDTM yields an overdetermined or underdetermined system of algebraic equations solved in the least square sense.

The IELDTM has proven to have excellent convergence properties by experimentally illustrating both h-refinement and p-refinement outcomes. A distinctive feature of the IELDTM over the existing numerical techniques is optimizing the local spatial degrees of freedom. It has been proven that the IELDTM provides more accurate results with far fewer degrees of freedom than the finite difference, finite element and spectral methods.

This study shows the derivation, applicability and performance of the IELDTM for solving 2D and 3D advection-diffusion equations. It has been demonstrated that the IELDTM can be a competitive numerical method for addressing high-space dimensional-parabolic partial differential equations (PDEs) arising in various fields of science and engineering. The novel ChSCM-IELDTM hybridization has been proven to have distinct advantages, such as continuous utilization of time integration and optimized formulation of spatial approximations. Furthermore, the novel ChSCM-IELDTM hybridization can be adapted to address various other types of PDEs by modifying the theoretical derivation accordingly.

This paper aims to introduce the usage of sensitivity analysis (SA) for the problem of faults identification in three-phase induction motors (IMs). These motors are susceptible to different kinds of faults that should be detected in a proper time to keep the systems working in a safety environment.

One of the effective approaches for faults identifications, which is presented in the literature, is a model-based strategy. This strategy mainly depends on using a software model to make an identification decision. Therefore, this work intends to examine the model sensitivity towards variables’ variation. The SA toolbox of Matlab R2017b package is used for this purpose since the Matlab software is a well-known environment, and it is easy for a nonstatistical person to deal with it. As a study case, open-circuit and stator inter-turn faults in the stator windings of a three-phase IM have been chosen.

The results show that the model-based strategy is considerably speed up by up to 30% when neglecting the trivial model’s parameters with the same accurate identification decision as compared with the results of this strategy without using the SA.

The novelty of this work is summarized in devoting the usage of SA in the field of faults identification to enhance the speed of final decision.

This study investigates the influence of social trust on the attainment of corporate environmental, social and governance (ESG) objectives.

This study conducts panel regression analysis on a distinctive dataset for 2009–2017 on Chinese firms.

The analysis reveals a significant positive association between social trust and firm-level ESG practices. Moreover, the impact of social trust on shaping ESG outcomes is further amplified by factors such as economic growth, corporate governance standards and institutional quality. This relationship remains statistically positive when the authors employ alternative measures and methodologies, such as the instrumental variables, propensity score matching and difference-in-differences approaches. Notably, the results of heterogeneity tests indicate that the Trust–ESG nexus is more prominent for state-owned enterprises and firms with substantial market capitalization, superior profitability and higher leverage.

This study expands the comprehension of the determinants of ESG and underscores the influential role of social trust as an informal institution in enhancing a firm's ESG performance.

The purpose of this study is to examine the effect of polarisation on trust in government.

The authors use the ordered probit technique to model trust as a function of polarisation and various control variables. The authors apply the instrumental variables approach to address potential endogeneity in polarisation, using ethnic diversity as an instrument.

The results reveal that an increase in polarisation reduces trust in central government. However, trust in local government is non-responsive to this polarisation. The estimations controlled for government performance, and the authors found a positive association between government performance and trust in government, which, however, does not alter the relationship between polarisation and trust in government.

In ethnically polarised nations, policymakers should consider decentralisation measures. This can help sustain trust and development support, particularly in regions where citizens prioritise ethnicity over nationality.

The social implications of this research underscore the importance of promoting trust in government to foster social cohesion and stability, particularly in ethnically diverse societies.

The authors find that increased ethnic polarisation reduces trust in the central government, particularly among those prioritising their ethnicity over nationality. This adds a non-performance dimension to government trust literature, suggesting that policies focusing solely on performance may yield limited results. The research extends beyond central government trust to include local governments. Unlike central government, local government trust remains tied to performance attributes unaffected by polarisation. Hence, investing resources through local governments is a viable strategy for enhancing citizen support while mitigating polarisation’s adverse effects.

In this study, a novel framework was proposed to assess the trust in e-government (e-Gov) services under an uncertain environment. The proposed framework was applied in Iranian municipality websites of e-Gov services to evaluate the readiness score of trust in e-Gov services.

A unique hybrid research methodology was proposed. In the first phase, a comprehensive set of indices were determined from an extensive literature review and finalized by employing the fuzzy Delphi method. In the second phase, interval-valued intuitionistic fuzzy set (IVIFS) -was utilized to model the problem's uncertainty with analytic called IVIFS- hierarchy process (AHP) to determine the importance of indices and indicators by assigning the weights. In the third phase, the fuzzy evaluation method (FEM) is followed for assessing the readiness score of indices in case studies.

The findings indicated that “Trust in government” is the most significant index affecting citizen's trust in e-Gov services while “Maintenance and support” has the least impact on user's intention to use e–Gov services.

The study contributes by introducing a unique research methodology that integrates three phases, including fuzzy Delphi, IVIFS AHP and fuzzy evaluation method. Moreover, the fuzzy sets theory helps to reach a more accurate result by modeling the inherent ambiguity of indicators and indices. Interval-valued intuitionistic fuzzy models the ambiguity of experts' judgments in an interval.

The study helps policy makers to monitor wider aspects of trust in e-Gov services as well as understanding their importance. The study enables policy makers to apply the framework to any potential case studies to evaluate the readiness score of indices and recognizing strengths and weakness of trust dimensions as well as recommending advice for improving the situation.

The study is one of the few to indicate significant indices of trust in e-Gov services in developing countries. The study shows the importance of indicators and indices by assigning a weight. Additionally, the framework can assess the readiness score of various case studies.

The purpose of this work is to study the relationships of trust in a local agri-food supply chain in Southern Brazil. In an unsustainable context, where the number of mariculturists is decreasing, the authors seek to identify what the factors are and how they contribute to this problem, as well as find solutions aimed at the sustainability of that chain.

The authors carried out qualitative research with 15 semi-structured interviews that took place in the year 2021. The thematic analysis of the results applied the IRAMUTEQ software and the assessment of the narratives was guided by prior thematic analysis.

The supply chain under investigation requires better organisation. Communication and interpersonal trust proved important in the relationship between producers and control bodies. The university, as a seed supplier, needs predictability and efficiency to convey inter-organisational trust. Informal relationships are interpersonal and extremely trust-based and inter-organisational trust increases the performance of establishments and promotes the development of innovative structures. Furthermore, in crisis periods interpersonal trust increases.

The results allow policymakers to plan better their actions and build more effective tactics in order to reach sustainable development. This work is also important for stakeholders and managers, as it guides improvements in management, governance and sustainability of agri-food supply chains.

An unprecedented research was done on the studied supply chain, knowing the relationships of trust among them, identifying peculiar partnerships and recognising some constructs and outcomes of trust.

This paper aims to analyze the relationships between human resource supply chain management (HRSCM), corporate culture (CC) and the code of business ethics (CBE) in the MENA region.

In this study, the author adopted a quantitative approach through an online Google Form survey for the data-gathering process. All questionnaires were distributed to the manufacturing and service firms that are listed in the Chambers of the Industries of Jordan, Saudi Arabia, Morocco and Egypt in the MENA region using a simple random sampling method. About 567 usable and valid responses were retrieved out of 2,077 for analysis, representing a 27.3% response rate. The sample unit for analysis included all middle- and senior-level managers and employees within manufacturing and service firms. The conceptual model was tested using a hypothesis-testing deductive approach. The findings are based on covariance-based analysis and structural equation modeling (SEM) using PLS-SEM software. The author performed convergent validity and discriminant validity tests, and bootstrapping was also applied.

The empirical results display a significant and positive association between HRSCM and the CBE. The CC and the CBE tend to be positively and significantly related. Therefore, HRSCM can play a key role in boosting and applying the CBE in firms. For achieving the firm purposes, more attention to the HR personnel should be paid to implement the CBE. The high importance of the CBE becomes necessary for both the department and the firm.

Such results can provide insightful information for HR personnel, managers and leaders to encourage them to develop and maintain an effective corporate code of conduct within their organizations.

This paper tries to explore the linkages between HRSCM, CC and CBE in the Middle East region due to the lack of research available that analyzes the relationship between them. Not only that, but it also offers great implications for Middle Eastern businesses.

This paper argues for the need to use multiple sources and methods that respond to research challenges presented by new forms of war. There are methodological constraints and contention on the superiority given to positivist and interpretivist research designs when doing fieldwork in war situations, hence there is a need to use integrated data generation techniques. The combined effect of severe limitations of movement for both the researcher and researched fragmented data because of polarized views about the causes of the war and unpredictable events that make information hard to come by militate against systematic, organised and robust data generation. The purpose of this paper, therefore, is to make fieldwork researchers understand significant research problems unique to war zones.

This research was guided by the postmodernist mode of thought which challenges standardised research traditions. Fieldwork experiences in Cabo suggest the need to use the composite strategies that rely on the theoretical foundation of integrative and creative collection of data when doing research in violent settings.

The fieldwork experiences showed that the standardised, conventional and valorised positivist and ethnographic research strategies may not sufficiently facilitate understanding of the dynamics of war. There should not be firm rules, guidelines or regulations governing the actions of the researcher in conflict. As such, doing research in violent settings require reflexivity, flexibility and creativity in research strategies that respond to rapid changes. Research experiences in Mozambique show the need to use blended methods that include even less structured methodologies.

Fieldwork experiences in Cabo challenges researchers who cling to standardised research traditions which often hamper awareness of new postmodernist mode of thought applicable to war settings. It is essential to study the nature of African armed conflicts by combining creativity and flexibility in the selection of research strategies.