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This study aims to regarding the application of traditional pulse frequency modulation control full-bridge LLC resonant converters in wide output voltage fields such as on-board chargers, there are issues with wide frequency adjustment ranges and low conversion efficiency.

To address these issues, this paper proposes a fixed-frequency pulse width modulation (PWM) control strategy for a full-bridge LLC resonant converter, which adjusts the gain by adjusting the duty cycle of the switches. In the full-bridge LLC converter, the two switches of the lower bridge arm are controlled by a fixed-frequency and fixed duty cycle, with their switching frequency equal to the resonant frequency, whereas the two switches of the upper bridge arm are controlled by a fixed-frequency PWM to adjust the output voltage. The operation modes of the converter are analyzed in detail, and a mathematical model of the converter is established. The gain characteristics of the converter under the fixed-frequency PWM control strategy are deeply analyzed, and the conditions for implementing zero-voltage switching (ZVS) soft switching in the converter are also analyzed in detail. The use of fixed-frequency PWM control simplifies the design of resonant parameters, and the fixed-frequency control is conducive to the design of magnetic components.

According to the fixed-frequency PWM control strategy proposed in this paper, the correctness of the control strategy is verified through simulation and the development and testing of a 500-W experimental prototype. Test results show that the primary side switches of the converter achieve ZVS and the secondary side rectifier diodes achieve zero-current switching, effectively reducing the switching losses of the converter. In addition, the control strategy reduces the reactive circulating current of the converter, and the peak efficiency of the experimental prototype can reach 95.2%.

The feasibility of the fixed-frequency PWM control strategy was verified through experiments, which has significant implications for improving the efficiency of the converter and simplifying the design of resonant parameters and magnetic components in wide output voltage fields such as on-board chargers.

In the measurement of liquid density and viscosity, the change of resonance parameters due to the parasitic parallel capacitance of resonator affects the measurement accuracy. To improve the accuracy, a method was proposed to compensate the parasitic parallel capacitance of resonator by adding an electrode.

The new electrode (compensation electrode) was added into resonant sensor to make compensation capacitance. The closer the compensation capacitance was to the parasitic parallel capacitance, the better compensation was. The structural parameters of resonant sensor with the compensation electrode were determined by the simulation and experiment.

The effect of this method was examined by the experiment. The relative errors of density and viscosity were less than 0.15, 0.5 % and standard deviations were less than 0.0004 g/cm³ and 0.005 mPas, respectively.

The experimental results show that this method is valuable for the parasitic parallel capacitance compensation of immersed resonant sensor.

This paper has not been published in other journals.

The purpose of this paper is to investigate the effect of NaCl solution with different concentrations on impact-sliding fretting corrosion behavior of Inconel 690TT steam generator heat transfer tubes.

The optical 3D profiler was used to measure the wear profile and calculated the wear volume. Corrosion behavior was studied using open circuit potential monitoring and potentiodynamic polarization testing. The morphologies and elemental distributions of wear scars were analyzed using scanning electron microscopy and energy-dispersive spectroscopy. The synergism of wear and corrosion was analyzed according to the ASTM G119 standard.

The corrosion tendency reflected by OCP and the corrosion current calculated by Tafel both increased with the increase of NaCl concentration. The total volume loss of the material increased with concentration, and it was known from the synergism that the volume loss caused by corrosion-enhanced wear accounted for the largest proportion, while the wear-enhanced corrosion also made a greater contribution to volume loss than tangential fretting corrosion. Through the analysis of the material morphologies and synergism of wear and corrosion, the damage mechanism was elucidated.

The research findings can provide reference for impact-sliding fretting corrosion behavior of Inconel 690TT heat transfer tubes in NaCl solution with different concentrations.

This paper aims to conceptually unite an ontology of cybernetics, bridging living and technical systems, to facilitate future epistemological and theoretical advancements applicable to highly technical societies by crafting a set of definitions that elucidate the nature of the world in which these systems operate.

The research uses a thematic synthesis of two systems/cybernetic traditions: complex adaptive systems and mechanology. The primary sources for this research were the main theses and correlated papers published in the Simondon case for mechanology, and the seminal literature preselected by the Santa Fe Institute for complex adaptive systems.

The study proposes the following concepts: Individuation: the emergence of new properties in an individual composed of synergistically related parts; Technical evolution: the notion that technical objects evolve into living beings; circular causality: the notion that feedback and feedforward processes shape the organisation and structure of systems and their relationship with the environment; The milieu refers to the part of the environment that has a relationship of co-production, co-dependency, and co-evolution with systems. Metastability is a state that transcends stability and instability and motivates changes in the system. Transduction is the cumulative process of individuation in which systems change structure and organization to maintain operational coherence with their surroundings.

The concepts the paper identifies can serve as a starting point for an extended study on the ontology of cybernetics or as the basis for an evolutionary epistemology both in humans and machines.

This study aims to improve detection efficiency of fluorescence biosensor or a graphene field-effect transistor biosensor. Graphene field-effect transistor biosensing and fluorescent biosensing were integrated and combined with magnetic nanoparticles to construct a multi-sensor integrated microfluidic biochip for detecting single-stranded DNA. Multi-sensor integrated biochip demonstrated higher detection reliability for a single target and could simultaneously detect different targets.

In this study, the authors integrated graphene field-effect transistor biosensing and fluorescent biosensing, combined with magnetic nanoparticles, to fabricate a multi-sensor integrated microfluidic biochip for the detection of single-stranded deoxyribonucleic acid (DNA). Graphene films synthesized through chemical vapor deposition were transferred onto a glass substrate featuring two indium tin oxide electrodes, thus establishing conductive channels for the graphene field-effect transistor. Using π-π stacking, 1-pyrenebutanoic acid succinimidyl ester was immobilized onto the graphene film to serve as a medium for anchoring the probe aptamer. The fluorophore-labeled target DNA subsequently underwent hybridization with the probe aptamer, thereby forming a fluorescence detection channel.

This paper presents a novel approach using three channels of light, electricity and magnetism for the detection of single-stranded DNA, accompanied by the design of a microfluidic detection platform integrating biosensor chips. Remarkably, the detection limit achieved is 10 pm, with an impressively low relative standard deviation of 1.007%.

By detecting target DNA, the photo-electro-magnetic multi-sensor graphene field-effect transistor biosensor not only enhances the reliability and efficiency of detection but also exhibits additional advantages such as compact size, affordability, portability and straightforward automation. Real-time display of detection outcomes on the host facilitates a deeper comprehension of biochemical reaction dynamics. Moreover, besides detecting the same target, the sensor can also identify diverse targets, primarily leveraging the penetrative and noninvasive nature of light.

Additive manufacturing (AM), also known as three-dimensional (3D) printing technology, has been used in the health-care industry for over two decades. It is in high demand in the health-care industry due to its strength to manufacture custom-designed and personalized 3D constructs. Recently, AM technologies are being explored to develop personalized drug delivery systems, such as personalized oral dosages, implants and others due to their potential to design and develop systems with complex geometry and programmed controlled release profile. Furthermore, in 2015, the US Food and Drug Administration approved the first AM medication, Spritam® (Apprecia Pharmaceuticals) which has led to tremendous interest in exploring this technology as a bespoke solution for patient-specific drug delivery systems. The purpose of this study is to provide a comprehensive overview of AM technologies applied to the development of personalized drug delivery systems, including an analysis of the commercial status of AM based drugs and delivery devices.

This review paper provides a detailed understanding of how AM technologies are used to develop personalized drug delivery systems. Different AM technologies and how these technologies can be chosen for a specific drug delivery system are discussed. Different types of materials used to manufacture personalized drug delivery systems are also discussed here. Furthermore, recent preclinical and clinical trials are discussed. The challenges and future perceptions of personalized medicine and the clinical use of these systems are also discussed.

Substantial works are ongoing to develop personalized medicine using AM technologies. Understanding the regulatory requirements is needed to establish this area as a point-of-care solution for patients. Furthermore, scientists, engineers and regulatory agencies need to work closely to successfully translate the research efforts to clinics.

This review paper highlights the recent efforts of AM-based technologies in the field of personalized drug delivery systems with an insight into the possible future direction.

Based on the comprehensive definition of accounting of Carnegie et al. (2021a, 2021b), this study examines how visual imagery can expand and enhance accountability to stakeholders and create room for more human-centric accounts. This study aims to understand how this use can elucidate and prompt interpretations of rhetorical features aimed at envisioning legitimacy and being perceived as accountable.

Following a methodological interpretative approach, this paper draws on a qualitative case study based on a Portuguese charity, the Santa Casa da Misericordia do Porto, from 2019 to 2021, including the COVID-19 crisis period, analysing visual rhetoric in annual and sustainability reports.

The study illuminates how the visual images interact and evoke shared cultural understandings, shaping meanings that can symbolically foster organisational legitimacy and envisions accountability. These symbolic and emotive elements capture and make visible social impacts and reflect broader societal concerns.

The study of visual images within the accounting context can enrich the understanding of accounting as a technical, social and moral practice, while expanding the scope of accountability and promoting a more human-centred approach to accounting. It also adds to the literature on the persuasiveness and rhetoric of accounting and reporting visualisations and on charities’ accountability in crisis period.

This paper aims to provide insights into the potential of digital technologies-based innovations for more inclusive healthcare by alleviating the affordability, accessibility and availability barriers to utilization of healthcare services. Also, it aims to provide insights into the potential of digital technologies-based innovations for more inclusive services, broadly.

A conceptual framework is inductively developed by analyzing real-world examples of digital technologies-based innovations for more inclusive healthcare through the lenses of economics of information in digital form and certain characteristics of services.

Concurrent implementation of digital technologies-based healthcare innovations with innovations and/or modifications in service processes can enable greater inclusivity by alleviating the affordability, accessibility and availability barriers to utilization of healthcare services.

Issues relating to inequities in healthcare, as a social problem, are the focus of research at multiple levels (e.g. global, national, regional and local) in several academic disciplines. In relation to the scope of the problems and challenges pertaining to providing quality healthcare to the unserved and underserved segments of society, worldwide, the contribution of the proposed framework to practice is modest. However, by highlighting the promise and potential of digital technologies-based innovations as solutions for alleviating barriers to affordability, accessibility and availability of healthcare services during various stages (prevention, detection, diagnosis, treatment and post-treatment follow-up) with illustrative vignettes and developing a framework, the article offers insights for future research. For instance, in reference to mission-driven social enterprises that operate in the product-market space for inclusive innovations under resource constraints, a resourcefulness-based view of the social enterprise constitutes a potential avenue for theory development and research.

Given the conceptual nature of the article, the implications for practice are limited to cognitive implications. Action implications (instrumental implications or implications for practice) are outside of the scope of the article.

Innovations that are economically viable, environmentally sustainable and socially impactful is one of the important issues of our times.

The proposed framework provides insights into the potential of digital technologies-based innovations for more inclusive healthcare by alleviating the affordability, accessibility and availability barriers in the context of emerging and less developed country markets and base of the pyramid segments of society in these markets.

This study aims to develop multifunctional, namely, superhydrophobic, flame-retardant and antibacterial, coatings over cotton fabric, using casein as green-based flame-retardant and silver nanoparticles as antibacterial agent by solution immersion method.

The cotton fabric is first coated with casein to make it flame-retardant. AgNPs synthesized using Cinnamomum zeylanicum bark extract is coated over the casein layer. Finally, stearic acid is used to coat the cotton to make it superhydrophobic. X-ray diffraction, transmission electron microscopy analysis and ultraviolet-visible spectroscopy are used to investigate the produced AgNPs. The as-prepared multifunctional cotton is characterized by scanning electron microscopy, energy dispersive X-ray analysis and attenuated total reflection-infrared studies. Flame test, limiting oxygen index test and thermogravimetric analyzer studies have also been performed to study the flame-retardant ability and thermal stability of treated fabric, respectively. The antibacterial effect of the coatings is evaluated by disc-diffusion technique. Water contact angle is determined to confirm the superhydrophobic nature of cotton fabric.

The outcomes of this study showed that the prepared multifunctional cotton fabric had maximum contact angle of greater than 150° with good flame retardancy, high thermal stability, greater washing durability and high antibacterial activity against the growth of Pseudomonas aeruginosa and Acinetobacter indicus. Additionally, the as-prepared superhydrophobic cotton showed an excellent oil–water separation efficiency.

The trilayered multifunctional cotton fabric has limiting washing durability up to 20 washing cycles. Treated functional fabric can be used as an antibacterial, therapeutic, water repellent and experimental protective clothing for medical, health care, home curtains and industrial and laboratory purposes.

The study brings out the robustness of this method in the development of multifunctional cotton fabrics.