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Biological oscillatory activity in neural networks has been intensively studied over the past years. Neuronal oscillations are the basis of many different behavioral patterns and sensory mechanism. Understanding the dynamic properties of these mechanisms is useful for analyses of biological functions and medical diagnoses. The dynamic characteristics of wake‐sleep circadian rhythms and ECG’s cardiac cycle data measured for normal subjects are identified here, using MA‐BP neural network model. It was found that dynamics of regular components can be captured by the model. The captured dynamics are kept in a steady state for some periods. The order of the MA neural network was suppressively controlled by the first 2∼3 orders. Hence it may be useful for medical diagnoses of circadian rhythms and heart related diseases.

It is of a great significance for the health monitoring of a liquid rocket engine to build an accurate and reliable fault prediction model. The thrust of a liquid rocket engine is an important indicator for its health monitoring. By predicting the changing value of the thrust, it can be judged whether the engine will fail at a certain time. However, the thrust is affected by various factors, and it is difficult to establish an accurate mathematical model. Thus, this study uses a mixture non-parametric regression prediction model to establish the model of the thrust for the health monitoring of a liquid rocket engine.

This study analyzes the characteristics of the least squares support vector regression (LS-SVR) machine . LS-SVR is suitable to model on the small samples and high dimensional data, but the performance of LS-SVR is greatly affected by its key parameters. Thus, this study implements the advanced intelligent algorithm, the real double-chain coding target gradient quantum genetic algorithm (DCQGA), to optimize these parameters, and the regression prediction model LSSVRDCQGA is proposed. Then the proposed model is used to model the thrust of a liquid rocket engine.

The simulation results show that: the average relative error (ARE) on the test samples is 0.37% when using LS-SVR, but it is 0.3186% when using LSSVRDCQGA on the same samples.

The proposed model of LSSVRDCQGA in this study is effective to the fault prediction on the small sample and multidimensional data, and has a certain promotion.

The original contribution of this study is to establish a mixture non-parametric regression prediction model of LSSVRDCQGA and properly resolve the problem of the health monitoring of a liquid rocket engine along with modeling the thrust of the engine by using LSSVRDCQGA.

The authors assess the development potential of cowpea beyond grain in local markets in Mali by: (1) identifying trader types and types of cowpea products sold; (2) examining trader roles; (3) estimating gross margins and their determinants; and (4) discussing policy opportunities to further develop the value chain.

The authors analyze data collected through observation and semi-structured questionnaires from 487 sellers in 26 markets, including market, seller, and product characteristics. The authors also calculate gross margins and conduct a regression analysis to identify influential factors.

The authors identify several types of cowpea sellers in local markets, including processor-retailers, retailers of fresh leaves and fodder, and grain retailers, collectors and wholesalers. Women dominate the marketing of processed products and fresh leaves. The marketing of boiled cowpeas offers retailers higher margin rates compared to fritters and pancakes. Grain sellers, who are mostly men, have lower margins but sell larger quantities. Processor-retailers bring more value to the cowpea value chain. Specialization of the seller in cowpea, regional location of the market and day of the market fair all influence gross margins.

Future work should explore consumer preferences for different types of cowpea products.

This study of the cowpea value chain in Mali has revealed the multidimensional character of the cowpea plant, which goes far beyond its grain and highlight the important roles played by women.

This chapter explores the symbiotic relationship between digitalization and sustainability in the context of Industry 4.0. Examining key technologies such as blockchain, artificial intelligence (AI), and the Internet of Things (IoT), this chapter unveils their transformative impact on industries, emphasizing the role of data-driven decision-making, supply chain transparency, and circular economy principles. Real-world case studies illustrate successful implementations, showcasing how organizations leverage digital twins, blockchain for supply chain transparency, and extended reality for sustainable training. The regulatory landscape emerges as a crucial factor, shaping the adoption of digital technologies for sustainability, while emerging trends like 5G, edge computing, and AI promise to redefine the future. As a conclusion, policymakers are urged to strike a balance between innovation and regulation, fostering an environment conducive to responsible digital practices. Industries are encouraged to embrace emerging trends, and researchers are invited to explore the synergies between 5G, edge computing, and AI for holistic sustainability solutions. Together, these efforts aim to propel Industry 4.0 toward a resilient and sustainable future.

The study proposes to determine the impending challenges to lean integration with Industry 4.0 (I4.0) in manufacturing that aims at achieving desired operational performance. Integrating lean and Industry 4.0 as the two industrial approaches is synergetic in providing operational benefits such as increasing flexibility, improving productivity, reducing cost, reducing delivery time, improving quality and value stream mapping (VSM). There is an urgent need to understand the integrated potential of OPEX strategies like lean manufacturing and also to determine the challenges for manufacturing SMEs and further suggest a strategic roadmap for the future.

The current work has used a combined approach on interpretative structural modeling (ISM) and fuzzy Matrice d'impacts croisés multiplication appliquée á un classment (MICMAC) approach to structure the multiple level analysis for the implementation challenges to integrate OPEX strategies with Industry 4.0.

The research has found that the indulgence of various implementation issues like lack of standardization, lack of vision and lack of trained support, all are the major challenges that inhibit the integration of OPEX strategies with I4.0 technologies in manufacturing.

The research has investigated the internal factors acting as a roadblock to lean and Industry 4.0 adoption. Further studies may consider external factors to lean and Industry 4.0 implementation. Also, further research may consider other operational excellence approaches and extend further to relevant sectors.

This study provides the analysis of barriers that is useful for the managers to take strategic actions for implementing OPEX strategies with I4.0 in smart manufacturing.

The research determines the adoption challenges towards the integrated framework. This is the first study to explore challenges in integrating OPEX strategies with I4.0 technologies in manufacturing SMEs.

The study measures the total systemic risks and connectedness across commodities, stocks, exchange rates and bond markets in Africa during the Covid-19 pandemic.

The study uses the Diebold-Yilmaz spillover and connectedness measures in a generalized VAR framework. The author calculates the net transmitters or receivers of shocks between two assets and visualizes their strength using a network analysis tool.

The study found low systemic risks across all assets and countries. However, we found higher systemic risks in the forex market than in the stock and bond markets, and in South Africa than in other countries. The dynamic analysis found time-varying connectedness return shocks, which increased during the peak periods of the first and second waves of the pandemic. We found both gold and oil as net receivers of shocks. Overall, over half of all assets were net receivers, and others were net transmitters of return shocks. The network connectedness plot shows high net pairwise connectedness from Morocco to South Africa stock market.

The study has implications for policymakers to develop the capacities of local investors and markets to limit portfolio outflows during a crisis.

Previous studies have analyzed spillovers across asset classes in a single country or a single asset across countries. This paper contributes to the literature on network connectedness across assets and countries.

Studies on transfers to a more regulated section show an increase in information disclosure and stocks’ liquidity levels. Classical theories suggest that volatility should also be reduced. This study aims to analyse the long-term effects of a section transfer to a more regulated section (TSE 1/TSE 2) on stock return volatility.

This study uses an empirical framework relying on two-sample t-tests and panel regressions. These use robust standard errors and control for fixed effects, day effects and macroeconomic factors. The return variance of comparable stocks’ benchmark sample, instead of market variance, is used as a control variable. Comparable stocks operate within the same industry and do not transfer during the sample period. The authors test our results’ robustness using generalized autoregressive conditional heteroskedasticity estimates.

The study’s main findings show that pre-transferred stocks are more volatile than the stocks’ benchmark sample. The transfer to a more regulated section leads to a gradual decrease in the total daily stock return volatility, intraday return volatility and overnight return volatility.

To the best of my knowledge, this study is the first to empirically address the volatility change caused by the stocks’ transfer to a more regulated section. This study highlights the benefits of choosing section transfers to reduce volatility.

This study aims to determine the pedagogical and socio-emotional impacts of school closures caused by the COVID-19 pandemic in Guinea.

A descriptive, survey-based methodology was used to collect quantitative and qualitative data directly from parents and caregivers. Between February 24 and March 13, 2022, data was gathered from a study population comprising 2,955 adults residing in five communes and five prefectures of Guinea.

Half of all respondents stated that school closures had no particular impact on children in their household, and 42% stated that no intentional pedagogical activities took place during school closures. Approximately 15% of respondents stated that children experienced boredom, loneliness, sadness, depression, stress and anxiety during the school closures.

The study underscores the significance of school closure readiness and interactive learning while revealing limited emotional impact on children. The findings, while specific to Guinea, provide a foundational understanding, highlighting the complexity of pandemic effects on education and the need for adaptive strategies in vulnerable regions.

To solve the problem, a mathematical model is proposed; it relies on a directed acyclic graph (DAG), in which arcs are used to indicate whether a pair of appointments can be assigned to the same route or not (and so to the same care worker). The proposed model aims at minimizing the personnel required to meet daily demand and balancing workloads among the workers while considering the varying traffic patterns derived from traffic congestion.

This paper aims at providing solution approaches for addressing the problem of assigning care workers to deliver home health-care (HHC) services, demanding different skills each. First, a capacity planning problem is considered, where it is necessary to define the number of workers required to satisfy patients' requests and then, patients are assigned to the care workers along with the sequence followed to visit them, thus solving a scheduling problem. The benefits obtained by permitting patients to propose multiple time slots where they can be served are also explored.

The results indicate that the problem can be efficiently solved for medium-sized instances, that is, up to 100 daily patient requests. It is also indicated that asking patients to propose several moments when they can receive services helps to minimize the need for care workers through more efficient route allocations without affecting significantly the balance of the workloads.

This article provides a new framework for modeling and solving a HHC routing problem with multiskilled personnel. The proposed model can be used to identify efficient daily plans and can handle realistic characteristics such as time-dependent travel times or be extended to other real-life applications such as maintenance scheduling problems.

In this study, the authors investigate a different routing and scheduling problem in the field of home health care (HHC) management system. The purpose of this paper is to route and schedule the workday of health workers, assign the patients to suitable health workers, make accurate decisions to minimize costs, provide timely services and, in general, enhance the efficiency of HHC centers.

A mixed-integer linear programming model is developed to assign health workers to patients. The model considers health professionals with different skills, namely nurses and physicians. Additionally, three groups of patients are considered: patients who need a nurse, patients who need a physician and patients who need both. In the third group, the nurse must be present at the patient’s home following the physician’s visit in order to perform the required tasks.

The results of this study show a reduction in costs which results from the fewer health workers employed and dispatched in comparison with traditional approaches. With the help of our solution approach and model, HHC centers may not only successfully reduce their costs but also manage to meet their patients’ demands by assigning suitable nurses and physicians.

Previous studies have often focused on problems involving only one group of health professionals and rarely address problems involving multiple groups. The authors consider this a shortcoming, because in many cases, patients should be visited several times and by various health professionals.