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The study aims to equip robots with the ability to precisely maintain interaction forces, which is crucial for tasks such as polishing in highly dynamic environments with unknown and varying stiffness and geometry, including those found in airplane wings or thin, soft materials. The purpose of this study is to develop a novel adaptive force-tracking admittance control scheme aimed at achieving a faster response rate with higher tracking accuracy for robot force control.

In the proposed method, the traditional admittance model is improved by introducing a pre-proportional-derivative controller to accelerate parameter convergence. Subsequently, the authors design an adaptive law based on fuzzy logic systems (FLS) to compensate for uncertainties in the unknown environment. Stability conditions are established for the proposed method through Lyapunov analysis, which ensures the force tracking accuracy and the stability of the coupled system consisting of the robot and the interaction environment. Furthermore, the effectiveness and robustness of the proposed control algorithm are demonstrated by simulation and experiment.

A variety of unstructured simulations and experimental scenarios are designed to validate the effectiveness of the proposed algorithm in force control. The outcomes demonstrate that this control strategy excels in providing fast response, precise tracking accuracy and robust performance.

In real-world applications spanning industrial, service and medical fields where accurate force control by robots is essential, the proposed method stands out as both practical and straightforward, delivering consistently satisfactory performance across various scenarios.

This research introduces a novel adaptive force-tracking admittance controller based on FLS and validated through both simulations and experiments. The proposed controller demonstrates exceptional performance in force control within environments characterized by unknown and varying.

The purpose of this paper is to investigate the impact of customer-focus on small medium enterprise (SME) performance from the perspective of a resource-based view (RBV).

This research study implemented a survey strategy to gather data from 255 respondents on the registered list of Ghana Enterprise Agency (GEA) in the eastern region of Ghana. Scales used to gather data were operationalized from previous research studies. A structural equation modeling (SEM) path analysis was used to estimate the impact of customer-focus on the performance of SMEs.

The outcomes of this study indicate that customer-focus has a significant positive impact on SME performance, hence backing the current demand for investigating the distinct influence of customer-focus on SME performance. The results show that customer-focus has a positive and significant relationship with financial performance, customer performance, internal business process performance and learning and growth performance, thus supporting the literature on the positive impact of customer-focus on SME performance. Therefore, customer-focus determinants used in this study, including co-creation, networking ties, customer insight and artificial intelligence marketing (AIM), are critical to the optimization of SME performance.

Notwithstanding the importance of this research study mentioned earlier, the study has limitations. Notably, the sample size of this study can be increased to capture SME respondents in other geographical zones that were not included in this study. Future research studies may address how business environment conditions moderate the relationship between customer focus and performance, and also the cause-effect of the relationship between customer focus and business environment conditions on SME performance.

The practical implications consist of two main items. First, this study empowers SME owners and managers to develop a customer focus technique as a central strategic goal in their quest for SME performance optimization. Second, SME owners and managers should progressively exploit the four determinants of customer focus which include co-creation, networking ties, customer insight and (AIM in order to accrue important resources for effective utilization of their customer focus competences as a way to enhance their performance.

This study is targeted at the sound development of SMEs to bring about poverty alleviation and employment. Poverty, unemployment and poor living standards are recognized as vital social challenges in most emerging economies. The establishment of customer focus as an important strategic capability provides opportunities for SME survival, profitability and growth.

Generally, the findings of this research study provide a strong backing to RBV perspective and the proposition that customer-focus and its determinants (i.e. co-creation, networking ties, customer insight and AIM) should be acknowledged as a vital strategic resource for optimizing the performance of SMEs. This research study also provides new knowledge contribution to the present body of knowledge on customer-focus orientation and management literature, particularly in the context of an emerging economy.

Understanding and tailoring the solidification characteristics and microstructure evolution in as-built parts fabricated by laser powder bed fusion (LPBF) is crucial as they influence the final properties. Experimental approaches to address this issue are time and capital-intensive. This study aims to develop an efficient numerical modeling approach to develop the process–structure (P-S) linkage for LPBF-processed Inconel 718.

In this study, a numerical approach based on the finite element method and cellular automata was used to model the multilayer, multitrack LPBF build for predicting the solidification characteristics (thermal gradient G and solidification rate R) and the average grain size. Validations from published experimental studies were also carried out to ensure the reliability of the proposed numerical approach. Furthermore, microstructure simulations were used to develop P-S linkage by evaluating the effects of key LPBF process parameters on G × R, G/R and average grain size. A solidification or G-R map was also developed to comprehend the P-S linkage.

It was concluded from the developed G-R map that low laser power and high scan speed will result in a finer microstructure due to an increase in G × R, but due to a decrease in G/R, columnar characteristics are also reduced. Moreover, increasing the layer thickness and decreasing the hatch spacing lowers the G × R, raises the G/R and generates a coarse columnar microstructure.

The proposed numerical modeling approach was used to parametrically investigate the effect of LPBF parameters on the resulting microstructure. A G-R map was also developed that enables the tailoring of the as-built LPBF microstructure through solidification characteristics by tuning the process parameters.

We propose a risk factor for idiosyncratic entropy and explore the relationship between this factor and expected stock returns.

We estimate a cross-sectional model of expected entropy that uses several common risk factors to predict idiosyncratic entropy.

We find a negative relationship between expected idiosyncratic entropy and returns. Specifically, the Carhart alpha of a low expected entropy portfolio exceeds the alpha of a high expected entropy portfolio by −2.37% per month. We also find a negative and significant price of expected idiosyncratic entropy risk using the Fama-MacBeth cross-sectional regressions. Interestingly, expected entropy helps us explain the idiosyncratic volatility puzzle that stocks with high idiosyncratic volatility earn low expected returns.

We propose a risk factor of idiosyncratic entropy and explore the relationship between this factor and expected stock returns. Interestingly, expected entropy helps us explain the idiosyncratic volatility puzzle that stocks with high idiosyncratic volatility earn low expected returns.

This study aims to analyze the relationships between cultural orientation and normative knowledge, in a direct and moderate way, on the whistleblowing intentions of accountants from Hispanic American countries.

This study used responses from a sample of 410 accountants, preparers and auditors of financial statements from Hispanic American countries. Descriptive statistics, nonparametric tests and structural equations with partial least squares algorithm were applied for data analysis.

The results emphasized the cultural positioning of horizontality, in which an individual perceives themselves as equals to their colleagues, allowing discussions on various aspects of individual behavior. The knowledge variable is proved to be important in explaining the intention to report and can also moderate the influence of cultural variables on intentions.

These findings contribute to the literature by offering a clearer definition the normative knowledge variable, and to organizations, which can explore the research’s evidence to improve their training and qualification programs, thereby generating significant knowledge for their employees.

Whistleblowing is the main tool for identifying organizational frauds, but it is differently perceived in several cultural contexts. The results demonstrated the ethical cultural positioning of these Hispanic American professionals in relation to cultural aspects of other countries. Some studies highlight knowledge as a relevant factor in the organizational environment, but this study innovates by testing and demonstrating its impact on whistleblowing and culture.

This paper aims to understand employees’ propensity to blow the whistle in two East African countries. This study develops a model of ethical decision-making (EDM) to assist management in predicting the probability of whistleblowing in Kenya and Uganda. It also seeks to find the moderating effect of perceived retaliation on whistleblowing intention.

This study administers a standardized questionnaire to employees in Kenya and Uganda to measure their perceptions about whistleblowing in their organizations. This study uses partial least square structural equation modeling to test the hypotheses. This study uses four constructs, namely, awareness, judgment, retaliation and likelihood, of blowing the whistle. These constructs are measured with multiple-item scales.

The results show that ethical awareness and judgment significantly increase willingness to engage in whistleblowing in East Africa. However, this study does not find a significant retaliation effect on whistleblowing intention. Instead, this study finds that awareness and judgment mediate between retaliation and willingness to engage in whistleblowing.

This study contributes to EDM topics. It advances the understanding of the whistleblowing concept, the retaliation effect and the reasons to encourage blowing the whistle in Africa. However, this study did not consider cultural factors, such as nationality, patriotism and ethnicity. Moreover, the results are only based on data from Uganda and Kenya and may not apply to other sub-Saharan nations.

These findings are particularly significant for managers and policymakers in East Africa, where fear of retaliation and lack of awareness are the main barriers to whistleblowing. The results may help managers develop human resource practices to include policies to support moral behavior. It may also provide insights to the policymakers to understand the factors that facilitate whistleblowing practices and help them to adopt new strategies or policies to stimulate whistleblowing culture.

This study is one of the initial empirical studies in the East Africa context to explore the EDM predictors and the impact of retaliation on the whistleblowing intention.

In recent decades, the student population in dormitories has increased notably, primarily attributed to the growing number of international students. Dormitories serve as pivotal environments for student development. The coordination and compatibility among students can significantly influence their overall success. This study aims to introduce an innovative method for roommate selection and room allocation within dormitory settings.

In this study, initially, using multi-attribute decision-making methods including the Bayesian best-worst method and weighted aggregated sum product assessment, the incompatibility rate among pairs of students is calculated. Subsequently, using a linear mathematical model, roommates are selected and allocated to dormitory rooms pursuing the twin objectives of minimizing the total incompatibility rate and costs. Finally, the grasshopper optimization algorithm is applied to solve large-sized instances.

The results demonstrate the effectiveness of the proposed method in comparison to two common alternatives, i.e. random allocation and preference-based allocation. Moreover, the proposed method’s applicability extends beyond its current context, making it suitable for addressing various matching problems, including crew pairing and classmate pairing.

This novel method for roommate selection and room allocation enhances decision-making for optimal dormitory arrangements. Inspired by a real-world problem faced by the authors, this study strives to offer a robust solution to this problem.

The proposed model aims to consider the flying hours as a criterion to initiate maintenance operation. Based on this condition, aircraft must be checked before flying hours threshold is met. After receiving maintenance service, the model ignores previous flying hours and the aircraft can keep on flying until the threshold value is reached again. Moreover, the model considers aircraft age and efficiency to assign them to flights.

The aircraft maintenance routing problem (AMRP), as one of the most important problems in the aviation industry, determines the optimal route for each aircraft along with meeting maintenance requirements. This paper presents a bi-objective mixed-integer programming model for AMRP in which several criteria such as aircraft efficiency and ferrying flights are considered.

As the solution approaches, epsilon-constraint method and a non-dominated sorting genetic algorithm (NSGA-II), including a new initializing algorithm, are used. To verify the efficiency of NSGA-II, 31 test problems in different scales are solved using NSGA-II and GAMS. The results show that the optimality gap in NSGA-II is less than 0.06%. Finally, the model was solved based on real data of American Eagle Airlines extracted from Kaggle datasets.

The authors confirm that it is an original paper, has not been published elsewhere and is not currently under consideration of any other journal.

Recent research has highlighted limited explicit knowledge of a company’s strategy on the part of its employees. The concept of Open Strategy has emerged as a promising approach to address and enhance knowledge and understanding of an organization’s strategy across all hierarchical levels. However, empirical investigations of the relationship between the degree of openness in a strategy process and employees’ strategy knowledge remain scarce. This study aims to fill this gap.

We conducted an online survey of individuals from various organizations, measuring the degree of openness of their strategy process and using regression analysis to determine the impact on strategy knowledge among the respondents. We operationalized strategy knowledge using two concepts. The first concept encompassed general knowledge of the employer’s strategy, mission, and vision. The second concept measured strategy knowledge in a more concrete manner by assessing factors such as the company’s markets, how it positions itself and its economic logic.

Our findings indicate that regardless of the level of hierarchy, the degree of openness has a strong positive effect on strategy knowledge. However, this effect is smaller when specific aspects of strategy knowledge are assessed compared to a general understanding of strategy. Our results highlight the potential of Open Strategy as an effective approach to enhancing employees’ knowledge of the employer’s strategy.

Our research demonstrates that the degree of openness in strategy processes significantly enhances strategy knowledge, thereby laying the groundwork for effective strategy implementation. The results highlight the importance of cultivating a culture of transparency, participation and inclusion of employees as well as ongoing communication to effectively integrate strategy into organizational practices. We offer practical implications for managers striving to optimize their strategic management processes.

Concrete, the second most used material in the world, surpassed only by water, relies on a vast amount of cement. The process of cement production emits substantial amounts of carbon dioxide (CO₂). Consequently, it is crucial to search for cement alternatives. Geopolymer concrete (GC) uses industrial by-product material instead of traditional cement, which not only reduces CO₂ emissions but also enhances concrete durability. On the other hand, the disposal of concrete waste in the landfills represents a significant environmental challenge, emphasising the urgent need for sustainable solutions. This study aimed to investigate waste concrete's best form and rate as the alternative aggregates in self-compacting and ambient-cured GC to preserve natural resources, reduce construction and demolition waste and decrease pertinent CO₂ emissions. The binding material employed in this research encompasses fly ash, slag, micro fly ash and anhydrous sodium metasilicate as an alkali activator. It also introduces the best treatment method to improve the recycled concrete aggregate (RCA) quality.

A total of25%, 50% and 100% of coarse aggregates are replaced with RCAs to cast self-compacting geopolymer concrete (SCGC) and assess the impact of RCA on the fresh, hardened and water absorption properties of the ambient-cured GC. Geopolymer slurry was used for coating RCAs and the authors examined the effect of one-day and seven-day cured coated RCA. The mechanical properties (compressive strength, splitting tensile strength and modulus of elasticity), rheological properties (slump flow, T500 and J-ring) and total water absorption of RCA-based SCGC were studied. The microstructural and chemical compositions of the concrete mixes were studied by the methods of energy dispersive X-Ray and scanning electron microscopy.

It is evident from the test observations that 100% replacement of natural aggregate with coated RCA using geopolymer slurry containing fly ash, slag, micro fly ash and anhydrous sodium metasilicate cured for one day before mixing enhances the concrete's quality and complies with the flowability requirements. Assessment is based on the fresh and hardened properties of the SCGC with various RCA contents and coating periods. The fresh properties of the mix with a seven-day curing time for coated RCA did not meet the requirements for self-compacting concrete, while this mix demonstrated better compressive strength (31.61 MPa) and modulus of elasticity (15.39 GPa) compared to 29.36 MPa and 9.8 GPa, respectively, for the mix with one-day cured coated RCA. However, incorporating one-day-cured coated RCA in SCGC demonstrated better splitting tensile strength (2.32 MPa) and water absorption (15.16%).

A potential limitation of this study on SCGC with coated RCAs is the focus on the short-term behaviour of this concrete. This limited time frame may not meet the long-term requirements for ensuring the sustained durability of the structures throughout their service life.

This paper highlights the treatment technique of coating RCA with geopolymer slurry for casting SCGC.