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Polymer laser powder bed fusion (PBF-LB/P) is an additive manufacturing technology that is sustainable due to the possibility of recycling the powder multiple times and allowing the fabrication of gears without the aid of support structures and subsequent assembly. However, there are constraints in the process that negatively affect its adoption compared to other additive technologies such as material extrusion to produce gears. This study aims to demonstrate that it is possible to overcome the problems due to the physics of the process to produce accurate mechanism.

Technological aspects such as orientation, wheel-shaft thicknesses and degree of powder recycling were examined. Furthermore, the evolving tooth profile was considered as a design parameter to provide a manufacturability map of gear-based mechanisms.

Results show that there are some differences in the functioning of the gear depending on the type of powder used, 100% virgin or 50% virgin and 50% recycled for five cycles. The application of a groove on a gear produced with 100% virgin powder allows the mechanism to be easily unlocked regardless of the orientation and wheel-shaft thicknesses. The application of a specific evolutionary profile independent of the diameter of the reference circle on vertically oriented gears guarantees rotation continuity while preserving the functionality of the assembled mechanism.

In the literature, there are various studies on material aging and reuse in the PBF-LB/P process, mainly focused on the powder deterioration mechanism, powder fluidity, microstructure and mechanical properties of the parts and process parameters. This study, instead, was focused on the functioning of gears, which represent one of the applications in which this technology can have great success, by analyzing the two main effects that can compromise it: recycled powder and vertical orientation during construction.

The purpose of this paper is to present current state of understanding on jet electrodeposition manufacturing; to compare various experimental parameters and their implication on as deposited features; and to understand the characteristics of jet electrodeposition deposition defects and its preventive procedures through available research articles.

A systematic review has been done based on available research articles focused on jet electrodeposition and its characteristics. The review begins with a brief introduction to micro-electrodeposition and high-speed selective jet electrodeposition (HSSJED). The research and developments on how jet electrochemical manufacturing are clustered with conventional micro-electrodeposition and their developments. Furthermore, this study converges on comparative analysis on HSSJED and recent research trends in high-speed jet electrodeposition of metals, their alloys and composites and presents potential perspectives for the future research direction in the final section.

Edge defect, optimum nozzle height and controlled deposition remain major challenges in electrochemical manufacturing. On-situ deposition can be used as initial structural material for micro and nanoelectronic devices. Integration of ultrasonic, laser and acoustic source to jet electrochemical manufacturing are current trends that are promising enhanced homogeneity, controlled density and porosity with high precision manufacturing.

This paper discusses the key issue associated to high-speed jet electrodeposition process. Emphasis has been given to various electrochemical parameters and their effect on deposition. Pros and cons of variations in electrochemical parameters have been studied by comparing the available reports on experimental investigations. Defects and their preventive measures have also been discussed. This review presented a summary of past achievements and recent advancements in the field of jet electrochemical manufacturing.

This paper aims to study the influence of microparticles on the surface cavitation behavior of 2Cr3WMoV steel; microparticle suspensions of different concentration, particle size, material and shape were prepared based on ultrasonic vibration cavitation experimental device.

2Cr3WMoV steel was taken as the research object for ultrasonic cavitation experiment. The morphology, quantity and distribution of cavitation pits were observed and analyzed by metallographic microscope and scanning electron microscope.

The study findings showed that the surface cavitation process produced pinhole cavitation pits on the surface of 2Cr3WMoV steel. High temperature in the process led to oxidation and carbon precipitation on the material surface, resulting in the “rainbow ring” cavitation morphology. Both the concentration and size of microparticles affected the number of pits on the material surface. When the concentration of microparticles was 1 g/L, the number of pits reached the maximum, and when the size of microparticles was 20 µm, the number of pits reached the minimum. The microparticles of Fe3O4, Al2O3, SiC and SiO2 all increased the number of pits on the surface of 2Cr3WMoV steel. In addition, the distribution of pits of spherical microparticles was more concentrated than that of irregularly shaped microparticles in turbidity.

Most of the current studies have not systematically focused on the effect of each factor of microparticles on the cavitation behavior when they act separately, and the results of the studies are more scattered and varied. At the same time, it has not been found to carry out the study of microparticle cavitation with 2Cr3WMoV steel as the research material, and there is a lack of relevant cavitation morphology and experimental data.

The purpose of this article’s research was threefold. Firstly, it aimed to investigate how social services professionals coped during the pandemic period by comparing their involvement in five different national contexts. Secondly, it analysed how these professionals have performed their duties according to the street-level bureaucracy theory. Finally, the third question examines social workers' strategies to guide their professional role when they may have had more discretion in their actions. The research also examined whether discretion has increased during this phase and, if so, how it has been exercised.

This article is based on the findings of the project called “Theory and Practice of Social Work in the World in Times of Pandemic”, which was funded by the International Association of Schools of Social Work (IASSW). The project involved 11 universities across five countries in Europe and Latin America, including Argentina, Brazil, Italy, Spain and Sweden. The research was conducted over 24 months to analyse the practices and measures taken to protect vulnerable people by adapting social services during the extraordinary period of the pandemic. In addition, the research explored how the awareness of emergency arose among social workers and how it influenced the services delivered from the perspective of the street-level bureaucracy theory. In different countries, the level of resourcefulness of services has varied based on their recognition of the severity of the pandemic and the impact of the government’s narratives. In some cases, these narratives have been conspiratorial or even anti-scientific. Additionally, there has been a reduction in the distance between professionals and clients, increased inequalities in access to services and a positive reassessment of the potential of new professional tools, such as digital social work, in establishing a trusting relationship.

As revealed in the interviews, the elements shaping this high degree of discretion among social workers can be classified into three levels: macro- and micro- (Saruis, 2015) plus a meso-level. Each level has four significant aspects. At the macro-level, these are legislation, public information, large associationism and integration of the social services-health system. At the meso-level, these are interpretations of role performance by managers technical equipment, self-organization and community action. The micro-level pertains to personal and family situations, emotions, ethics and social workers' direct relationships with those in charge.

This study investigated how social workers responded to the Covid-19 pandemic. The data gathered sheds light on their understanding of the situation, as well as the differences in experiences across the five countries studied. However, it is essential to note that the findings may not apply to all situations or countries. Nevertheless, this research serves as a stepping stone for future studies to delve deeper into the results and explore them in greater detail .

The study highlights the crucial role of social workers as street-level workers in managing, negotiating and creating meaning in the interaction between professionals and the people they serve. This is especially relevant in Latin America. Additionally, the study emphasizes the significance of social workers as policy actors and the political nature of social work practice. The findings also underscore the importance of effective communication and collaboration between social workers, their teams and the organizations they work for. The sources cited in the study are Barberis and Boccagni (2014) and Cuadra and Staaf (2014). The research has also underscored the potential of social service workers to build networks and cooperate. Such networking can play a vital role in implementing their acquired knowledge. The study has, therefore, emphasized the importance of social workers being an integral part of the societies they serve. They need to continuously enhance their communication skills, using all the necessary tools to gain a comprehensive and updated understanding of the evolving needs of their clients. Integrating digital social work as a mode of service provision has emerged as a crucial aspect, especially in the three European countries observed. This approach has demonstrated its potential and is expected to continue being a part of services to some extent, even after the return to normalcy. However, it is essential to ensure that the accessibility and proximity of services are not compromised in any way.

An unexpected result was observed during the research: the pandemic circumstances have led to valuable reflections. These reflections can help in rethinking and recreating social services. Social workers have been given a unique opportunity to return to the essence of their profession and develop less bureaucratic and more humane ways of working. This experience has also enabled them to recover a closer relationship with the people they serve. To sum up, this study emphasizes that social workers, when given more leeway in their work, rely on cultivating and upholding relationships with other professionals, organizations and stakeholders to stay connected with the community they serve. This is crucial for ensuring the delivery of effective and sustainable social services.

The research employed a thematic analysis approach (Bazeley, 2007) to identify themes related to the concept of consciousness as derived from the field experiences of social workers. Additionally, an in-case and cross-case analysis method (Fereday and Muir-Cochrane, 2006) was used to connect themes related to individual experiences with those gathered from the overall experiences.

Despite being a Muslim-dominated country, Bangladesh has widely embraced traditional microfinance since its inception in the mid-1970s. However, Islamic microfinance, which has a lot to offer to the poor, is still in its infancy and has yet to gain momentum in the country. Therefore, the purpose of this study is to analyze the importance of Islamic microfinance and propose alternative Shariah-compliant microfinance models in Bangladesh.

This study is based on the desk research method, which relies on existing literature to collect secondary data on key concerns of traditional microfinance programs. In addition, institutional-level secondary data were also collected from the Microcredit Regulatory Authority (MRA) of Bangladesh. Guided by the Maqasid-al-Shariah, this study then proposes several Islamic microfinance models to overcome selected challenges faced by the microfinance industry in Bangladesh.

This study suggested three composite Shariah-compliant microfinance models, which are likely to help the underprivileged and thus ensure the achievement of the sustainable development goals in Bangladesh. The first model explained how the operational strategy of incumbent microfinance institutions (MFIs) could be restructured, while the second proposed the organizational strategies for establishing a new MFI. The third model used the notion of Sadaqah (charity) to address the multiple borrowing issues of the industry. Meanwhile, the successful transformation of the conventional microfinance industry to an Islamic one is dependent on the effective collaboration between the regulatory authorities, practitioners and MFIs.

Albeit the paucity of literature on the topic, the findings of this study will guide policymakers/practitioners in designing relevant microfinance models to help transform conventional microfinance into Islamic microfinance in Bangladesh.

This study, a conceptual paper, analyses the growth of curation in tourism and hospitality and the curator role in selecting and framing products and experiences. It considers the growth of expert, algorithmic, social and co-creative curation modes and their effects.

Narrative and integrative reviews of literature on curation and tourism and hospitality are used to develop a typology of curation and identify different curation modes.

Curational techniques are increasingly used to organise experience supply and distribution in mainstream fields, including media, retailing and fashion. In tourism and hospitality, curated tourism, curated hospitality brands and food offerings and place curation by destination marketing organisations are growing. Curation is undertaken by experts, algorithms and social groups and involves many of destination-related actors, producing a trend towards “hybrid curation” of places.

Research is needed on different forms of curation, their differential effects and the power roles of different curational modes.

Curation is a widespread intermediary function in tourism and hospitality, supporting better consumer choice. New curators influence experience supply and the distribution of consumer attention, shaping markets and co-creative activities. Increased curatorial activity should stimulate aesthetic and stylistic innovation and provide the basis for storytelling and narrative in tourism and hospitality.

This is the first study of curational strategies in tourism and hospitality, providing a definition and typology of curation, and linking micro and macro levels of analysis. It suggests the growth of choice-based logic alongside service-dominant logic in tourism and hospitality.

This paper aims to concentrate on recent innovations in flexible wearable sensor technology tailored for monitoring vital signals within the contexts of wearable sensors and systems developed specifically for monitoring health and fitness metrics.

In recent decades, wearable sensors for monitoring vital signals in sports and health have advanced greatly. Vital signals include electrocardiogram, electroencephalogram, electromyography, inertial data, body motions, cardiac rate and bodily fluids like blood and sweating, making them a good choice for sensing devices.

This report reviewed reputable journal articles on wearable sensors for vital signal monitoring, focusing on multimode and integrated multi-dimensional capabilities like structure, accuracy and nature of the devices, which may offer a more versatile and comprehensive solution.

The paper provides essential information on the present obstacles and challenges in this domain and provide a glimpse into the future directions of wearable sensors for the detection of these crucial signals. Importantly, it is evident that the integration of modern fabricating techniques, stretchable electronic devices, the Internet of Things and the application of artificial intelligence algorithms has significantly improved the capacity to efficiently monitor and leverage these signals for human health monitoring, including disease prediction.

This paper aims to systematically review and synthesize existing research on learning-driven strategic renewal and examines the findings to elucidate the dimensions, antecedents, mechanisms and consequences associated with learning-driven strategic renewal, thereby addressing gaps in the existing literature.

This research covers learning-driven strategic renewal from 1992 to 2022, using hybrid snowball sampling techniques and Boolean searches on the Scopus and Web of Science databases to extract 49 papers.

This review proposes an organizing framework for learning-driven strategic renewal, building upon existing literature. The framework identifies various dimensions of the process, including antecedents, mechanisms and consequences. The antecedents are categorized into individual, organizational and external factors. The mechanisms for learning-driven strategic renewal were explored within the context of Crossan’s established 4I framework, which serves as a lens for emphasizing the balance between exploratory and exploitative learning. Within this framework, intuiting, interpreting, integrating and institutionalizing are the four “Is” that guide the renewal process. These mechanisms require a robust system to enforce the prescribed processes effectively, thereby contributing to long-term firm performance and sustainability.

Despite using search terms similar to those in existing literature on strategic renewal, the scope and depth of this study may be limited. Further research may benefit from bibliometric screening or more refined inclusion criteria.

While there has been extensive research into both organizational learning and strategic renewal, no coherent framework links them. This study fills this gap by building a framework that identifies connections between these two concepts, providing valuable insights that may be used to foster successful strategic renewal efforts. The review offers valuable knowledge and understanding of the subject matter, serving as useful guidance for effectively driving renewal initiatives within organizations.

Static inverters are very important for the emergency energy distribution system of aircraft and similar machines. At the same time, the electrical energy produced at high frequency for electrical devices is used to reduce the weight of the cables in the aircraft and spacecraft because of the skin effect. In the high-frequency system, a thinner cable cross-section is used, and a great weight reduction occurs in the aircraft. So, fuel economy, less and late wear of the materials (landing gear, etc.) can be obtained with decreasing weight. This paper aims to present the development of a functional multilevel inverter (FMLI) with fractional sinus pulse width modulation (FSPWM) and a reduced number of switches to provide high-frequency and quality electrical energy conversion.

After the production of FSPWM for FMLI with a reduced component, which, to the best of the authors’ knowledge, is presented for the first time in this study, is explained step by step, and eight operating states are given according to different FSPWMs operating the circuit. The designed inverter and modulation technique are compared by testing the conventional modular multilevel inverter on different loads.

According to application results, it is seen that there is a 50% reduction in cross-section from 100 Hz to 400 Hz with the skin effect. At 1000 Hz, there is a 90% cross-section reduction. The decrease can be in cable weights that may occur in aircraft from 10 kg to 100 kg according to different frequencies. It causes less harmonic distortion than conventional converters. This supports the safer operation of the system. Compared to the traditional system, the proposed system provides more amplitude in converting the source to alternating voltage and increases the efficiency.

FSPWM is developed for multilevel inverters with reduced components at the high frequency and cascaded switching studies in the power electronics of aircraft.

Although the proposed system has less current and power loss as mentioned in the previous sections, it contains fewer power elements than conventional inverters that are equivalent for different hardware levels. This not only reduces the cost of the system but also provides ease of maintenance. To reduce the cable load in aircraft and create more efficient working conditions, 400 Hz alternative voltage is used. The proposed system causes less losses and lower harmonic distortions than traditional systems. This will reduce possible malfunctions and contribute to aircraft reliability for passengers and cargo. As technology develops, it is revealed that the proposed inverter system will be more efficient than traditional inverters when devices operating at frequencies higher than 400 Hz are used. With the proposed inverter, safer operation will be ensured, while there will be less energy loss, less fuel consumption and less carbon emissions to the environment.

The proposed inverter structure shows that it can provide energy transmission for electrical devices in space and aircraft by using the skin effect. It also contains less power elements than the traditional inverters, which are equivalent for different levels of hardware.

This research studies the development of the evolving dynamic system model and explores the important elements or factors and what detailed attributes are the main influences model in achieving the success of a business, industry and management. It also identifies the real and major differences between static and dynamic business management models and the detailed factors that influence them. Later, this research investigates the benefits/advantages and limitations/disadvantages of some research studies. The studies conducted in this research put more emphasis on the capabilities of system dynamics (SD) in modeling and the ability to measure, analyse and capture problems in business, industry, manufacturing etc.

The research presented in this work is a qualitative research based on a literature review. Publicly available research publications and reports have been used to create a research foundation, identify the research gaps and develop new analyses from the comparative studies. As the literature review progressed, the scope of the literature search was further narrowed down to the development of SD models. Often, references to certain selected literature have been examined to find other relevant literature. To do so, a supporting tool (that connects related articles) provided by Google Scholar, Scopus, and particular journals has been used.

The dynamic business and management model is very different from the static business model in complexity, formality, flexibility, capturing, relationships, advantages, innovation model, new goals, updated information, perspective and problem-solving abilities. The initial approach of a static system was applied in the canvas business model, but further developments can be continued with a dynamic system approach.

Based on this study, which shows that businesses are developing more towards digitalisation, wanting the ability to keep up with the era that is moving so fast and the desire to increase profits, an instrument is needed that can help describe the difficulties of the needs and developments of the future world. This instrument, or tool of SD, is also expected to assist in drawing future models and in building a business with complex variables that can be predicted from the beginning.

This study will contribute to the SD study for many business incubator research studies. Many practical in business incubator management to have a benefit how to achieve the business performance management (BPM) in SD review.

The significant differences between static and dynamics to be used for business research and strategic performance management. This comparative study analyses some SD models from many authors worldwide. Their goals behind their strategic business models and encounter for their respective progress.