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Traditional level inverter technology has drawbacks in the aspect of Total harmonic distortion (THD) and switching losses for higher frequencies. Due to these drawbacks, two-level inverters have become unprofitable for high-power applications. Multilevel inverters (MLIs) are used to enhance the output waveform characteristics (i.e. low THD) and to offer various inverter topologies and switching methods.

MLIs are upgraded versions of two-level inverters that offer more output levels in current and voltage waveforms while lowering the dv/dt and di/dt ratios. This paper aims to review and compare the different topologies of MLI used in high-power applications. Single and multisource MLI's working principal and switching states for each topology are demonstrated and compared. A Simulink model system integrated using detailed circuit simulations in developed in MATLAB®–Simulink program. In this system, a constant voltage source connected to MLI to feed asynchronous motor with squirrel cage rotor type is used to demonstrate the efficacy of the MLI under different varying speed and torque conditions.

MLI has presented better control and good range of system parameters than two-level inverter. It is suggested that the MLIs like cascade-five-level and NPC-five-level have shown low current harmonics of around 0.43% and 1.87%, respectively, compared to two-level inverter showing 5.82%.

This study is the first of its kind comparing the different topologies of single and multisource MLIs. This study suggests that the MLIs are more suitable for high-power applications.

The purpose of this study was to bring library practitioners and researchers together to develop two co-designed tools for helping library practitioners gain a more holistic understanding of families in underserved groups and identify their values with the goal of developing more relevant learning experiences for them. The co-designed tools were then tested with Master’s of Library and Information Science (MLIS) students at two universities, whose feedback yielded several valuable findings and informed revisions to the tools.

A participatory, design-based approach was used throughout the study, both with engaging library practitioners in the co-design of different tools and processes introduced in the Toolkit, and to help MLIS students and library practitioners test the tools and provide feedback on the tool revisions.

Students indicated that the tools helped them develop a deeper understanding of underserved groups and their values and gave the students the time and space to reflect on their understanding of the socio-cultural and value contexts of their communities and the values they hold.

This study can help libraries more effectively design strengths-based learning experiences that are meaningful and relevant to underserved groups and their values, particularly for children and families from underserved communities.

The purpose of this paper is to design a cascaded Multilevel inverter with reduce number of switches for high power applications. This paper came up with an innovative three-phase multilevel inverter (MLI) topology, which is a cascaded structure based on classical three-legged voltage source inverter (VSI) bridges as an individual module. The prominent advantage of this topology is that it requires only one direct current (DC) link system. The main characteristic of it is that a higher number of voltage levels can be achieved with considerably a smaller number of semiconductor switches, which improves the reliability, power quality, cost and size of the system significantly.

The individual modules are cascaded through three-phase transformers to provide higher voltage at the output with the higher number of voltage levels. In this work, the phase-shifted pulse width modulation technique is implemented to verify the result.

The proposed topology is compared with three-phase cascaded H-bridge MLI (CHB-MLI) and a modified CHB-MLI topology and found better in many aspects. The proposed MLI can produce a higher number of voltage levels with fewer semiconductor switches and associated triggering circuitry. As the device count in the proposed MLI is less compared to other MLI discussed, it tends to have less switching and conduction loss which increases the efficiency and reliability. As the number of level increases, the voltage profile and the total harmonic distortion of the proposed MLI improves.

This is a transformer-based modular cascaded MLI, which is based on classical VSI bridges. Here in this topology, a single module provides all three phases. So, a single string of cascaded modules is enough for three-phase multilevel voltage generation.

Multilevel inverters become very popular in medium voltage applications owing to their inherent capability of reconciling stepped voltage waveform with reduced harmonic distortion and electromagnetic interference. They have several disadvantages like more number of switching devices required and devices with high voltage blocking and need additional dc sources count to engender particular voltage. So this paper aims to propose a novel tri-source symmetric cascaded multilevel inverter topology with reduced number of switching components and dc sources.

A novel multilevel inverter has been suggested in this study, offering minimal switch count in the conduction channel for the desired voltage level under symmetric and asymmetric configurations. This novel topology is optimized to prompt enormous output voltage levels by employing constant power switches count and/or dc sources of voltage. The topology claims its advantages in generating higher voltage levels with lesser number of voltage sources, gate drivers and dc voltage sources.

The consummation of the proposed arrangement is verified in Matlab/Simulink R2015b, and an experimental prototype for 7-level, 13-level, 21-level, 29-level, 25-level and 49-level operation modes is constructed to validate the simulation results.

The proposed topology operated with six new algorithms for asymmetrical configuration to propel increased number of voltage levels with reduced power components.

The purpose of this study is to investigate a practical strategy for integrating application programming interfaces (APIs) and standard interchange protocols (SIPs) within library and information services. This study will seek to determine how such an integration strategy can improve access to resources, enhance the user experience, optimize library operations and improve the overall efficiency of library services.

A qualitative approach to research will be used in this study. This study will be based on the review of relevant literature sources, case studies and real examples. The data analyzes to determine the practical application of SIP and API integration and identify the major methods, approaches and processes used by libraries to successfully implement integration projects.

This study explores that library and information services may achieve numerous benefits from API and SIP integration. The cases describe how libraries have managed to improve access, user experience, operational efficiency and general performance. Libraries have integrated APIs and SIP to create seamless search experiences, establish communication networks in real-time, and develop automated workflows and customer services. API and SIP integration will transform libraries in future.

The originality of this study is the focus of the API and SIP integration. While other authors have discussed the concept of integration from a theoretical standpoint, this study presents practical recommendations and implementation advice for librarians and researchers. This study uses real cases and examples to illustrate how libraries today have managed to improve their operations with the help of APIs and SIP integration.

This study aims to analyze the adoption of open access (OA) publishing in social sciences within central universities in India, focusing on various aspects such as the growth of OA literature, the use of different OA routes and collaboration patterns in OA publications.

Ten central universities were selected based on their rankings in the National Institute Ranking Framework 2022. Data on OA publishing in social sciences were collected from the Social Science Citation Index of the Web of Science (WoS) database using the advanced search query “(CU=India OR AD=India) AND PY=(2003–2022) NOT PY=(2023).” Data analysis was conducted using MS Excel (v16.0), BibExcel (version 2017), Biblioshiny (version 4.1.2) and Google Open Refine (version 3.7).

The study found that 30.40% of total publications were OA, with BHU as leading institute in OA publishing. OA publishing in social sciences saw a consistent increase, peaking in 2022 with 209 publications. “Sustainability” and “Plos One” were among the top ten journals, with 103 and 34 OA papers, respectively. OA publications had a higher mean citation rate than closed access publications. Collaboration with seven and nine authors had higher mean citation rates, while six-author collaborations were lower. Indian researchers received the most citations collaborating with the USA, UK and Australia. The Netherlands and Saudi Arabia received the fewer citations, when collaborating with Indian authors.

The study’s main limitation is its reliance on WoS data, excluding many OA publications from smaller or specialized journals. Additionally, the focus on high-ranked central universities may not represent the entire academic landscape, as OA publishing patterns vary across other institutions and disciplines.

The study’s findings suggest that advancing OA publishing in social sciences at Indian universities requires raising awareness of OA concepts, enhancing institutional support and policies and informing researchers about funding opportunities. Emphasizing Gold OA and funding publication fees can broaden access to research. Universities with low OA ratios should adopt similar policies, mandate public research deposits and develop technical infrastructure. Encouraging multi-author collaborations can boost research impact and citation rates. Insights from the study can help institutions and policymakers shape effective OA strategies, enhancing the visibility and impact of social science research.

This is the first study analyzing the adoption of OA in the field of social sciences in high-ranked central universities in India. It has implications for promoting OA and increasing accessibility to research outputs. Universities with higher OA ratios can lead in this regard and encourage others to adopt similar practices for overall OA growth.

This study aimed to examine the impact of perceived risks of COVID-19 and users’ intention to continually use social media for COVID-19 information, thereby revealing social media users’ perceptions and behaviors regarding the pandemic.

The Health Belief Model was used to develop the research model. Data were collected from social media users in Korea using an online survey.

The findings showed that social media users’ intention to continually use social media for COVID-19 information explained 46.5% of the variance in their perceived severity, perceived susceptibility, perceived benefits, and perceived barriers. The degree of impact and relationships varied across the constructs. Two age groups were examined, and it transpired that perceived risks and perceived use were more highly recognized by young users than old users.

This study focused on Korean social media users, providing valuable insights but limiting its generalizability. The proposed research model and methodology can include participants from various countries or cultures to enhance global relevance and diversified perspectives on how perceived risks impact social media use for health information.

This study’s findings can be used to provide tailored health information services to those with different levels of perceived risks, social media use, and different age groups.

This study adopted the Health Belief Model to understand users’ perceptions of COVID-19 information on social media and examined users’ intentions to continue using social media as a channel for COVID-19 information.

Middle leadership is difficult to define and fathom as these roles are fluid, adapting to the context of individual schools. However, little is known about the relationships among middle leadership, teacher commitment and job satisfaction in the field of education. The purpose of this paper is to propose a conceptual framework on the mediating role of teacher job satisfaction in the relationship between middle leadership and teacher commitment in schools based on past research, particularly in the context of schools.

A review of literature was undertaken to develop the conceptual framework.

Findings suggested that middle leadership can positively influence teacher commitment via the mediating effect of teacher job satisfaction.

The value of this paper lies in understanding middle leadership as a salient factor in influencing teacher commitment via teacher job satisfaction. This paper’s framework lays a strong foundation for the expansion of the middle leadership knowledge base on middle leadership as well as for future theory development and debate.

The primary objective was to develop a user-centered mobile health application (app) tailored to the specific health information needs of among immigrant women from diverse backgrounds in Korea.

In-depth interviews were conducted with 24 immigrant women to gain insights into their health information-seeking behavior. Based on the findings, a mobile app was designed and developed. A beta version of the app underwent validation by an MD and seven expert reviewers who assessed the app for content accuracy and conformance to mobile heuristics. Last, immigrant women (n = 12) evaluated the usability of the app.

The study revealed that the interviewed immigrant women had strong health information needs related to pregnancy and parenting. Most of them used multiple sources to find and verify health information. Language barriers were identified as a major obstacle to accessing and evaluating health information. The results of the user test indicated that the app effectively facilitated study participants' search for reliable health information, meeting their specific needs.

This research extended the literature by addressing the limited availability of mobile apps tailored to the health information needs of immigrant women in Korea.

By incorporating multilingual support and focusing on pregnancy and parenting information, the health app serves as a valuable tool to bridge the gap in health information access and to facilitate the well-being of immigrant women in the country.

The study aims to determine the level of e-reading habits and preferred electronic reading materials among nursing college students. The study examines students’ problems and difficulties using electronic resources and their knowledge of electronic literacy. Over the recent years, worldwide interest in reading electronic books has skyrocketed.

This study uses a survey research design and a structured closed-ended questionnaire as the data collection instrument. The sample population consists of college students. The study uses a quantitative method to investigate this population’s e-reading habits and preferred electronic reading materials.

The study findings indicate that while students prefer electronic resources, they need help accessing them due to various factors such as cost and availability. The survey results show that libraries must subscribe to a broader range of electronic resources, and academics and publishers must promote open-access articles to address these limitations.

The study addresses a current issue of students’ reading habits and preferred electronic reading materials and examines the limitations they face in accessing these resources. This research concludes that 21st-century students have transitioned from traditional to digital reading habits. They have a preference for electronic resources but their access to these resources is limited.