Medium Power Research Articles

Single-Phase Robust Charger with High Power Quality for Electric Vehicle Application

The widespread use of electric vehicles (EVs) necessitates the development of a robust charging infrastructure. The goal of this research paper is to create a high-quality, single-phase charger for electric cars. The purpose of this design is to provide a charger that is both fast and efficient but also protects against power quality problems including harmonics, power factor correction, and voltage variations. A single-phase–single-stage improved power quality EV charger for small and medium power applications has been designed and simulated. A single DC-DC converter is utilized for constant charging and improved power quality operation. The charger presented exhibits improved power quality as sinusoidal current is drawn from the utility grid supply with the total harmonic distortion (THD) in compliance with the IEEE 519 and IEC 61000-3-2 standards. In order to charge the battery of an electric vehicle, most two-stage converters first use a boost converter for power factor correction (PFC), and then they use a DC-DC converter that can accept any input voltage. These two-stage conversions are inefficient and use more parts than necessary. This work proposes a PFC converter based on a single-stage switching inductor Cuk converter, which has the advantages of high step-down gain, low current stress, high efficiency, and a small number of components. The suggested converter’s operational analysis and design equations are performed in continuous current mode. The proposed converter is the subject of extensive mathematical modelling, analysis, simulation, and experimentation presented in this study. With both constant voltage (CV) and constant current (CC) loads, the proposed converter’s performance is analysed with regard to power quality indices like voltage total harmonic distortion (THD), current THD, and total power factor. Additionally, in CV mode and CC mode, the suggested converter’s dynamic performance with battery charging is evaluated in relation to the extensive supply changes. The developed charger presents a reliable and efficient solution for EV charging, fostering the transition to a cleaner and more sustainable transportation system.

Social Media Marketing Initiatives and Brand Loyalty

Background: Social media advertising strategies have radically changed how brands interact with consumers and cultivate brand loyalty. The study's principal objective was to identify the influence of social media marketing activities on consumer brand loyalty toward shopping goods. Methods: The study used primary data from a structured survey questionnaire with the six-point Likert scale sent to Nepalese customers. The study's sampling was convenient, and the Kathmandu-based location was chosen as the sample site. The study's population was the consumers of consumer shopping goods. People who purchase consumer shopping items were given 600 surveys, but only 395 usable questionnaires were collected. Results: Through the path analysis, the influence of the credibility of social media significantly and positively influenced brand loyalty (β = 0.165, p < 0.05). It was also found that the informativeness of social media significantly impacted brand loyalty toward consumer shopping goods (β = 0.130, p < 0.05). Likewise, it was also investigated whether social media entertainment significantly impacts brand loyalty (β = 0.426, p < 0.05) toward consumer shopping goods in the Nepalese market. Conclusion: By leveraging the power of social media venues to engage with customers, deliver pertinent content, and create personalized experiences, businesses may cultivate a strong emotional connection with their target audience, increasing brand loyalty and trust. Novelty: The study results show how future researchers and business people can look at the new conditions for market growth.

Social Media in Crisis Communication: A Case Analysis of the 2023 Kahramanmaraş Earthquakes

This study examines the role of Twitter/X, a news platform, in crisis communication. The aim of the study is to contribute to the literature on crisis communication by understanding the importance, effectiveness, and applicability of social media. For this purpose, a qualitative research was conducted to determine how X was used as a communication tool during crises, specifically focusing on a case analysis of the Kahramanmaraş earthquakes. Within the scope of the research, 182 tweets shared between February 6th and 13th, 2023, from the official X account of the Disaster and Emergency Management Presidency (AFAD), were examined. Content analysis method was employed to analyze the tweets, focusing on content, frequency of sharing, and interaction rate. The research findings indicate that AFAD's tweets were categorized into four main themes: "information on processes, support services, announcements, and disinformation and communication." The findings suggest that the posts were predominantly made during the initial period of the crisis characterized by high uncertainty, with the most shared content focusing on search and rescue operations. Another research objective was to determine the interaction rate of AFAD's crisis communication messages. Accordingly, it is noteworthy that the theme with the least frequency of sharing, "disinformation and communication," received the highest interaction from users. The findings of this study, which focuses on the transformative power of social media in crisis communication, confirm that the need for reliable communication channels and verified information/sources increases during crises, and it confirms the significant role of institutional social media accounts in combating disinformation.

Enhancing Medium Term Wind Power Forecasting Accuracy With Dual Stage Attention Based TCN-GRU Model and White Shark Optimization

This research introduces a creative strategy for addressing the challenges of wind power predicting, crucial for effective renewable energy integration into the power grid. We propose a dual-stage attention-based Temporal Convolutional Network and Gated Recurrent Units (ATCN-AGRU) method for predicting wind energy over the medium term. In the first stage, a local attention mechanism captures fine-grained details and local dependencies, while the second stage employs a global attention mechanism to emphasize broader context and long-range dependencies within the data sequence. Our experimentation employs wind turbine data at 1-hr resolution, examining various time horizons from 24 hr to 1 week to assess multi-step forecasting precision and computational efficiency. Through rigorous statistical assessments, we demonstrate the model’s validity, with the mean absolute percentage errors (MAPE) consistently below 9% for week-ahead forecasting. Model parameters were fine-tuned using white shark optimization (WSO), enhancing convergence and overall performance. The proposed hybrid model significantly outperforms standard forecasting methods, achieving a maximum MAPE of 8.07% for week-ahead forecasting and a minimal 4.44% for day-ahead forecasting. To test the model’s stability, we extend the experiment to month-ahead forecasting, with the mean absolute error (MAE) ranging from 2.42 to 6.2% for weekly predictions.

КОМПОЗИТНЫЕ МАТЕРИАЛЫ НА ОСНОВЕ ПОЛИМЕР/ГРАФЕНА В РОБОТИЗИРОВАННЫХ УСТАНОВКАХ ПОЖАРОТУШЕНИЯ

It is shown that numerous devices contain their own electrical power sources that use a significant number of bipolar transistors and thyristors of medium and high power, which require additional cooling in the form of external radiators to remove excess heat. For their manufacture, in addition to traditional alloys based on aluminum, materials such as polymers with fillers of high thermal conductivity are promising. A composite surface saturation technology is proposed that uses boron nitride nanocrystals to reduce thermal resistance at the interface. It has been established that the heat-conducting properties both along and across the polymer fibers, as the content of the nanocrystalline form of boron nitride increases to 25 %, they increase and reach a value of 21,3 W/(m K). This value is more than twice the possible maximum thermal conductivity coefficient in the absence of a graphene layer: 9,8 W/(m K) with a boron nitride mass content of up to 50 %. Due to its characteristics, polymer/graphene composite material has promise as a material for cooling devices with high energy density.

Features of ignition and combustion of low-grade coal mixed with pyrolysis liquid

THE RELEVANCE of the study lies in the need to use pyrolysis liquid from wood processing for combustion in boilers of medium and low power as part of mixtures with coal. The unpredictability of the ignition and combustion properties of such mixtures, as well as the lack of calculation methods, predetermined a predominantly experimental approach to the study of these processes. At the same time, for the widespread implementation of such technological solutions in practice, it is necessary to have relatively simple methods for assessing the ignition and combustion characteristics of these components. THE PURPOSE. Synthesize samples of pyrolysis liquid from two different sorts of wood and perform their characterization. Develop an experimental method for studying ignition and combustion characteristics of pyrolysis liquid mixed with low-reactivity coal. Perform research on ignition delay times and the composition of released gas-phase products. Determine the main mechanisms of action of the components in the mixture of low-grade coal with pyrolysis liquid they’re during ignition and combustion. METHODS. The study was carried out using an experimental technique based on a high-temperature muffle furnace equipped with a high-speed video camera and a once-through gas analyzer. RESULTS. The article presents the dependences of the ignition delay times and the concentration curves of gas-phase products released during combustion of mixtures of low-grade coal and two types of pyrolysis liquid in the temperature range of the heating medium 600-800 °C and additive concentrations from 0 to 20 wt.%. Linear approximation dependences of ignition delay times on additive concentrations were obtained, and the mechanism of action of the additive during combustion was formulated. CONCLUSION. It was found that an increase in the concentration of the additive in the mixture leads to a stable decrease in the ignition delay times, while the amount of gas-phase products formed varied additively with respect to the composition of the mixture. The shape of the concentration curves for the release of CO and NOx indicates the independent action of the components of the mixture. The mechanism of action of additives was proposed. It was based on significant contribution of their evaporation process followed by combustion in the gas phase, which, in turn, initiats the ignition of coal.

Quantity and Size of Titanium Particles Released from Different Mechanical Decontamination Procedures on Titanium Discs: An In Vitro Study.

Complications such as peri-implantitis could ultimately affect the survival of a dental implant. The prevention and treatment of peri-implant diseases require managing bacterial biofilm and controlling environmental risks, including the presence of pro-inflammatory titanium (Ti) particles in the peri-implant niche. Objectives included the evaluation of the size and quantity of Ti particles released from moderately roughened Ti surfaces during common mechanical surface decontamination methods. One hundred and forty moderately roughened Ti discs were divided into seven groups (n = 20 per group); six groups received mechanical decontamination procedures (ultrasonic scaling (US) with a metal tip and poly-ether-ketone (PEEK) under low and medium power settings, air-polishing with erythritol powder, and Ti brush), and the control group underwent air-water spray using a dental triplex. The rinsing solution was collected for Ti mass analysis using inductively coupled plasma mass spectrometry (ICPMS), as well as for Ti particle size and count analysis under scanning electron microscopy (SEM) with energy-dispersive spectroscopy (EDS). US metal tip instrumentation generated 34.00 ± 12.54 μg and 34.44 ± 6.08 μg of Ti under low and medium power settings, respectively. This amount of Ti generation was significantly higher than other instrumentation methods. The mean Ti particle size of the US groups ranged from 0.89 ± 0.27 μm to 1.25 ± 0.24 μm. No statistically significant difference was found in the particle size among US groups and Ti brush group (1.05 ± 0.11 μm), except for US with the PEEK tip, where a significantly smaller mean particle diameter was found at the low power setting (0.89 ± 0.27 μm). Mechanical instrumentation can produce Ti particulates and modify the implant surfaces. US using a metal tip generated the highest amount of Ti with smaller Ti size particles compared to all other commonly used mechanical surface instrumentations. The EDS analysis confirmed Ti in PEEK US tips. It can be suggested that deterioration from the PEEK US tip and Ti brush, as observed under SEM, is an additional source of Ti release during Ti surface decontamination.

Middle power plays: How and when Mach middle managers use downward abuse and upward guanxi to gain and maintain power

SummaryGiven Machiavellianism's strong historical and theoretical roots in power and politics, there are surprisingly few empirical studies, if any, that directly examine how Machiavellians attain and maintain power in organizations. Understanding this is important because Machiavellian employees have managed to effectively gain power to reach managerial positions of influence in organizations despite their negative reputation. Further, there are contradictory theories and peripheral empirical findings that suggest they gain power either by strategically forging important connections or through coercive force. We propose that a Mach middle manager perspective can help illuminate which power‐gaining strategy is used. Drawing from the Machiavellianism literature and power dependence theory, we theorize how Mach middle managers gain coercive power through abusive supervision on those with less power (their subordinates), while building close guanxi with those with more power (their senior manager) to obtain relational empowerment. Moreover, we theorize that they maintain power by increasing both power‐gaining strategies when Mach middle managers perceive a high threat to hierarchy from subordinates, suggesting these parallel relations are positively connected. We found support for our theoretical model using data from a multi‐confederate experimental lab study and two multi‐wave field studies. The theoretical and empirical implications of our findings are discussed.

Study of optical properties birefringent of hema - DR13

The following paper is a detailed study of the optical properties of HEMA-DRI3 from optical birefringence can be induced azopolymeric material. Based on the method of two-photon absorption, anisotropy is generated due to the reorientation of the chromophores in the sample of HEMA-DR13. Using allow-power laser He-Ne, and a laser Nd-YAG medium power, it was possible to implement an optical system which allows observing the subsequent quantification of photoinduced bireftingence in said material. Subsequently comparing the results obtained with different theoretical models, thereby determining the characteristic times (time of excitation and relaxation time) of HEMA-DR13. Additionally, a study of the response signal based on the excitation power and the temperature of the material being able to obtain the relationship between this variables and the intensity of bircfringence.

Unleashing the power of social media: examining farmers’ adoption for agriculture knowledge exchange

Purpose This study uses a comprehensive theoretical framework that combines social cognitive theory and neighborhood effect to investigate the influence of neighborhood effects on farmers’ outcome expectations, observational learning and self-efficacy. This study aims is to analyze the mechanisms that underlie the adoption of social media by farmers for knowledge exchange in the agricultural context. Specifically, this research explores the role of neighborhood effects, outcome expectations, observational learning and self-efficacy in shaping farmers’ decision-making process regarding the use of social media platforms for exchanging agricultural knowledge. Design/methodology/approach The study data was collected through a sample survey conducted among 570 agricultural households residing in the provinces of Thai Nguyen, Cao Bang, Bac Kan and Phu Tho, located in the northern region of Vietnam. To analyze the data, structural equation modeling was used as the statistical technique of choice. Findings The findings of the study indicate a significant influence of neighborhood effects on outcome expectations, observational learning and self-efficacy. These factors, derived from social cognitive theory, also exhibit a positive association with farmers’ adoption of social media for knowledge exchange. Additionally, the study highlights that neighborhood contribute to a favorable adoption of social media among farmers via outcome expectations, observational learning, and self-efficacy. Research limitations/implications The study is limited in examining farmers’ social media adoption for agriculture knowledge exchange in Northern mountainous area of Vietnam. This study could be replicated across various regions or nations, providing comparative insights into the adoption of social media among farmers for knowledge exchange. Practical implications The study findings suggest practical and innovative means to promote farmers’ social media adoption for agriculture knowledge exchange. Originality/value This study presents a pioneering approach by integrating social cognitive theory and neighborhood effect to elucidate the factors influencing farmers’ adoption of social media for the purpose of agriculture knowledge exchange.

Framing Long Covid through Patient activism in the United States: Patient, Provider, Academic, and Policymaker Views

In 2020, when COVID-19 patients first recognized their complex and progressive symptoms, patient activists defined “Long Covid” on social media. While patient support groups are by no means new, the predominance of online support groups and those leveraging the power of social media has become a defining characteristic of Long Covid. In this article, we argue that naming Long Covid served as a powerful conduit of legitimacy for patient activists in media, medicine, and policy. We conducted 57 in-depth qualitative interviews with patients (n = 22), clinicians (n = 20), and policy and academic experts (n = 15). We found naming was not a primary area of contention. In contrast, patients found pride and a sense of identity within the terms. Many clinicians struggled with diagnostics because Long Covid lacks clear biological tests, while patients were consistently disappointed by the lack of positive tests and clarity around their symptomatology. The heterogeneity of the Long Covid experience, as well as the diversity of symptoms, further provides opportunities for contestation and disbelief among clinicians and policymakers not only in diagnostics but also in disability rights. Thus, the power of patient activism has transformed how the condition is perceived among and between patients, clinicians, policymakers, and the media in unprecedented ways that will likely have longstanding impacts on how IACCs are viewed in medicine and the public alike.

Blue Economic Beacon: Red And White Leads The Way Through Niche Diplomacy

This research has a specific objective to analyze the Indonesian government's strategy in realizing sustainable marine development based on its role as a middle power country. The author uses the theoretical framework of middle power identity and niche diplomacy to analyze the problems in this study. This research is a type of qualitative research that is explained using the explanatory method. Based on the results of the research, the Indonesian government's strategy is to prioritize sustainable marine development in national marine policy and also commit to contributing to the world's sustainable marine development with the blue economy principle. This commitment will be realized by increasing cooperation in the marine sector at the bilateral, multilateral and regional levels. Specifically, the form of the realization of this commitment is that Indonesia has become the strategy of the Indonesian government to realize sustainable marine development is to become the initiator of the formation of cooperation forums (coalition building), to become the contact person for countries in the interest of sustainable marine development (bridge builder), and to uphold international norms in the marine sector for the common good (catalyst).

South Korea’s middle power diplomacy and the South China Sea disputes

ABSTRACT The middle power concept is versatile enough to categorise any states in the middle range of the world order that display certain behavioural characteristics known as middle power behaviours. Meanwhile, the adoption of the middle power concept as an explicit policy position by Korean IR scholars and policy researchers can shape and influence the actual policy practice as South Korea’s academic discussions on ‘middle power diplomacy knowledge’ (MPD) have advanced with the purpose of serving its national interests. This research sought to better conceptualise South Korea’s middle power diplomacy particularly on the South China Sea disputes between the USA and China and determine whether or not it is essential for its national interests through active Korean IR scholars’ and policy researchers’ perspectives. It found that there is more uncertainty or concern about employing ‘middle power diplomacy’ due to their assessment of finding greater drawbacks than benefits. Yet, the utmost reason behind such discrepancy stems from the epistemic fallacies prevalent in the middle power scholarship. Ultimately, discussions on South Korea’s middle power diplomacy should begin with the awareness of such fallacies and attempt to address them by critically examining the ontology of South Korea’s middle power categorisation, which leads one to question what kind of reality entails South Korea’s being a ‘middle power’ in the SCS disputes and, from there, determine its appropriate role.

Sustainable Media and Green Innovation: The Impact of Sustainable Atmosphere and Environmental Regulation on Manufacturing Enterprises

This study proposes a research framework for media attention towards green innovation of manufacturing enterprises based on the theory of stakeholders and legitimacy. We examine the potential effect of media attention on the manufacturing industry and make a multidimensional heterogeneity analysis with a sample of Chinese manufacturing enterprises during 2011–2019. Our results show an inverted U-shaped relationship between various attentions of media and green innovation. We find that the early attention of the media can expand the green innovation ability of manufacturing enterprises. However, the excessive attention of the media later may decrease the green behavior of enterprises. The legitimacy pressure of media attention on enterprises helps enterprises carry out green innovation and reduce false green innovation activities. In addition, the sustainable construction, environmental regulations, and sustainable social atmosphere focused on by the media will have a positive effect on the green innovation of enterprises. We suggest that recognizing the importance and potential power of sustainable media, environmental regulations, and sustainable atmosphere in green technology is a key component of the ecological inclusive path to promote the achievement of sustainable development goals.

ATTENTION TO PROBLEMATIC SOCIAL GROUP REPRESENTATION IN GUIDANCE FOR USING MASS MEDIA IN ENGLISH EDUCATION

While media studies amply document problematic social group representation in mass media materials, how English language educators are equipped to address these issues when they engage in the common practice of appropriating such artifacts for teaching is unclear. This research responds by collecting 319 prominent Internet sources providing guidance on using mass media materials for language learning and subjecting them to a content analysis. This analysis draws upon ten forms of problematic social group portrayal in the mass media as a conceptual lens. Analysis results indicate little attention to ableism, ageism, Christonormativity, classism, colorism, gender bias, heternormativity, lookism/sizeism, racism, and urbanormativity with articles universally acclaiming the integration of mass media materials into language teaching, primarily on the grounds of “authenticity.” Defined as materials authored by and for native speakers, this is an authenticity insensitive to authentic social group representation. This research is significant because of teacher reliance on the Internet as a source of materials, because of the global reach of English language teaching, the power of mass media, especially for youth socialization, and because there is a lack of previous research concerning how language teachers are trained to consider problematic social group representation in mass media artifacts.

EKONOMI POLITIK PERLINDUNGAN HAK KEKAYAAN INTELEKTUAL: STUDI KASUS KEBIJAKAN PUBLISHER RIGHTS AUSTRALIA TERHADAP GOOGLE DAN FACEBOOK

Australian news media publishers are facing serious challenges as Google and Facebook emerge as digital platforms in the Australian media industry. They have transformed into the main pillars of media industry as they monopolize distribution and monetization of news content as well as the digital advertising market, thus dominate Australia’s digital market share. Their power and dominance in controlling the flow of information and digital advertising have drawn attention of the Australian government. In response, the Australian government enacted the publisher rights policy through adoption of the News Media and Digital Platforms Mandatory Bargaining Code (NMBC). Google and Facebook reacted strongly against the NMBC and threatened to close the services in Australia. This research aims to explain the reasons behind Australia’s enactment of the publisher rights policy against Google and Facebook. Using the analytical descriptive research methods combined with theory of regulatory mercantilism, concept of digital sovereignty, and concept of intellectual property rights, this study argues that enactment of the publisher rights policy is due to the imbalance of bargaining power between the Australian news media publishers and Google and Facebook. In addition, this policy was enacted due to the reduction in traditional revenue received by the traditional news media publishers as a result of declining advertising revenue, content purchases, and subscriptions that pose a threat to sustainability of Australia’s news media industry. Lastly, the adoption of the publisher rights policy is due to the centralized media power of Google and Facebook which endangers diversity of Australian news media.

Seeking information about Covid-19 vaccine on social media: a moderated mediated model of antecedents and behavioral outcomes

PurposeSocial media have been playing a critical role in seeking and sharing health related information and consequently shaping individuals’ health behaviors. This study investigates how information seeking about Covid-19 vaccine on social media is related to vaccine receiving intentions. The study furthers explores the association of trust in social media and uncertainty about Covid-19 with information seeking and the moderating role of prior social media experience on this association.Design/methodology/approachWe developed a questionnaire and collected data from 525 educated social media users through “Google Forms.” Further, we applied ordinary least squares (OLS) regress to test the study hypothesis.FindingsWe noted that trust in social media and uncertainty about Covid-19 vaccine positively influenced information seeking which further positively affected vaccine receiving intentions. However, the moderating effect of prior social media experience was not only noted as weak but also found negatively affecting the associations of trust in social media and uncertainty about Covid-19 vaccine with information seeking.Research limitations/implicationsThe findings provide insights into understanding of public perceptions regarding Covid-19 vaccine in the cultural contexts of a developing country. Further, it informs about the public patterns of seeking information related to health issues on social media, an understanding which may likely benefit policymakers, health care providers and researchers to understand the antecedents and behavioral outcomes of seeking information through social media during health crisis. The study also elucidates the leveraging power of social media to motivate the public to accept the Covid-19 vaccines.Originality/valueThe study uniquely combines the antecedents and behavioral outcomes of information seeking through social media in the particular context of Covid-19. It further extends the literature by introducing the conditional role of prior social media experience.

Understanding the power of social media: an investigation with opinion mining

This work investigates how sentiment analysis in a simulated social network can identify users' opinions for various purposes, such as market research and brand monitoring. The goal is to test the effectiveness of automated analysis of large volumes of unstructured data. The research uses mixed methods and is descriptive, exploring the influence of sentiment patterns among users and reviewing data analysis on social networks and natural language processing. As a result, it was possible to have a richer understanding of frequently used words, as well as the associations between different themes and feelings in the simulated community.

Contesting Narratives: A Comparative Analysis of Indian, Pakistani and Kashmiri Print Media Framing of the Abrogation of Article 370

The revocation of Article 370 by the Indian government in August 2019, stripping Jammu and Kashmir of its semi-autonomous status, dramatically exacerbated tensions in the long-standing Kashmir conflict. This decisive unilateral action triggered a harsh security crackdown and communications blackout in the Kashmir Valley. Given the disputed territory's centrality to Indo-Pak relations and regional stability, the framing of this pivotal event by Indian, Pakistani and Kashmiri media assumed immense geopolitical significance. This study comparatively examined the dominant frames employed by elite English newspapers in all three stakeholder regions - The Hindu in India, Dawn in Pakistan, and Kashmir Times representing the local Kashmiri press. Underpinned by framing theory, a deductive qualitative content analysis revealed starkly divergent framings aligned with the respective nationalistic stances. The findings expose how media outlets strategically amplified certain aspects while marginalizing others to promote polarizing master narratives reflecting national interests regarding the Kashmir dispute. The implications underscore media's power to construct contested realities serving partisan interests in protracted geopolitical conflicts. To uphold ethical journalism principles, prevent further escalation, and promote inclusive human rights framing, the study recommends transnational collaboration between Indian, Pakistani and Kashmiri outlets rooted in objectivity and impartiality.

Cross-Strait Tensions and Southeast Asia's Middle Powers: A Singaporean Perspective

Cross-Strait Tensions and Southeast Asia's Middle Powers: A Singaporean Perspective