Power Strategy Research Articles

Short-term interval prediction strategy of photovoltaic power based on meteorological reconstruction with spatiotemporal correlation and multi-factor interval constraints

Short-term photovoltaic (PV) power interval prediction provides a basis for day-ahead power dispatching and generation planning. However, the current gridded numerical weather prediction (NWP) has poor matching in specific PV stations, and the lack of consideration of PV power mutation characteristics and historical correlation in interval prediction, which further limit the improvement of PV power prediction accuracy. In this regard, this paper proposes a novel short-term interval prediction strategy for PV power. Based on the second-order extended hidden Markov model (HMM), the key meteorological elements of the PV station with poor matching are reconstructed. In the interval prediction, the trend mutation and historical correlation characteristics of the PV sequence are fully considered, and a PV power interval prediction method that combines three factors such as trend change, time correlation and numerical mutation is proposed. The proposed method is applied to a PV station in Jilin, China. The results show that compared with other methods, the RMSE of the proposed method is reduced by 5.3 % on average, and the CWC is reduced by at least 2.1 %, which verifies the effectiveness of the proposed method.

The makings of a moral superpower: Swedish good international citizenship as middle-power nation brand

ABSTRACT Sweden has consistently performed positively in global assessments of its nation brand and its contributions to global order. A testament to a century of agile image construction, Sweden’s ‘moral superpower’ branding has evolved in recent decades to encompass ideals of the ‘good international citizen’ that continue to elevate its status amongst middle powers. Despite Sweden’s moral record being imperfect, this article examines the reasons and methods behind Sweden’s overwhelming successes in political nation branding, asking whether these strategies are still viable into the mid-twenty-first century. The article frames Sweden’s moral nation brand through the concept of the good international citizen, which is identified as an integral component of effective middle power strategy in the contemporary international system. As recent geopolitical events have forced Sweden to reconsider its foreign policy objectives and align with more realist, hard power agendas, it argues that of leaning into the good international citizen as normative/behavioural nation branding is required to bridge the gap between Swedish imagery and reality.

China’s ‘Stadium Diplomacy’ in West Asia and North Africa: Soft-power Tool for Political and Economic Influence

China’s ‘Stadium Diplomacy’ in West Asia and North Africa (WANA) is a soft power strategy used to increase its regional political and economic influence. This strategy is part of a broader trend in which China increasingly uses soft power tools to project its global influence. Chinese companies are involved in building and funding large-scale sports facilities and stadiums used as venues for major international sports events. By investing in sports infrastructure, China can project an image of economic and technological prowess and gain access to raw materials, mineral resources, and markets while fostering closer diplomatic ties with countries in the region. Nevertheless, there are also concerns that China’s soft power efforts are being used to mask more strategic and geopolitical goals. While stadium diplomacy can be an effective soft power tool for building economic relationships and increasing influence, it must also be scrutinised and understood in the context of China’s broader strategic goals and interests.

Cambodia’s soft power strategy: hosting the 2023 Southeast Asian games

Cambodia’s soft power strategy: hosting the 2023 Southeast Asian games

The effect of internet use on the health of middle-aged and older adults: evidences from China general social survey

BackgroundAccording to the United Nations classification of aging societies, China is rapidly transitioning into a moderately aging society, facing significant challenges related to population aging. Concurrently, China is actively implementing the Internet Power Strategy and the Internet Plus action plan, which are profoundly transforming the daily lives of individuals, including their health status. However, research on the impact of internet use on the health of middle-aged and older adults has not reached a consensus. This study aims to investigate the effects of internet use on the health of middle-aged and older adults, as well as the mechanisms and heterogeneity of these effects.MethodsThis study utilized data from the China General Social Survey conducted in 2018, which includes a sample of 6470 individuals. Self-rated health, mental health, and objective health were used as key health indicators, with internet use identified as the primary independent variable. The study aims to analyze the impact of internet use on the health status of middle-aged and older adults through the application of an ordered probit model and instrumental variable methods.ResultsThe results indicate that internet use has a significant positive impact on the health of middle-aged and older adults, with significance at the 1% level. This finding has passed a series of robustness tests. Mechanism analysis reveals that information acquisition is a crucial mediating mechanism between internet use and the health of middle-aged and older adults. This suggests that increased internet use enhances information access, thereby improving health outcomes. Furthermore, heterogeneity analysis shows that the impact of internet use on health is more pronounced among individuals living in rural areas, western regions, low-income groups, and those aged under 60, compared to their counterparts in urban areas, eastern regions, higher-income brackets, and those aged 60 and above.ConclusionInternet use can improve the health of middle-aged and older adults. Therefore, government departments, senior universities, communities, and families should collaborate to actively conduct digital skills training for older adults. Additionally, efforts should be accelerated to adapt electronic products to be more elder-friendly, helping older adults overcome the digital divide and thereby reducing health inequalities among middle-aged and older groups.

The invisible hand of Doctor Zhivago: reception of a soft power tool

ABSTRACT In the tumultuous era of the Cold War, Boris Pasternak's novel Doctor Zhivago found itself at the epicenter of an ideological battle. When the Soviet authorities deemed it an ‘evil libel against the USSR’ and prohibited its publication, the CIA recognized its ‘great propaganda value’ and spearheaded its dissemination in foreign editions, harnessing the novel as a potent soft power tool. Through an interdisciplinary approach, this paper analyzes the influence of a reverse kind of cultural diplomacy related to the translation, diffusion, and promotion of Doctor Zhivago in the West. Drawing from paratextual material in the form of press reviews in Italian, French, English and Dutch from both quantitative and qualitative perspectives, it assesses how the sense of confidence, attraction and prestige as pillars of soft power strategies are reflected in the reception of the novel’s translations. The study concludes by offering a nuanced understanding of how the large-scale diffusion of the novel was perceived, highlighting that the translations played a secondary role in the strategy and served as vehicles to amplify the impact of Pasternak’s Nobel Prize, thereby extending its influence globally.

Md. Nazmul ISLAM, Power of Bonding and Non-Western Emerging Great Powers Engagement: Comparing China and India’s Soft Power Strategy in Pakistan

Power of Bonding and Non-Western Emerging Great Powers Engagement: Comparing China and India’s Soft Power Strategy in Pakistan by Md. Nazmul Islam is a scholarly exploration that pioneers new perspectives in International Relations. It offers a unique and fresh insight into how non-Western emerging great powers, specifically China and India, utilize soft power strategies to engage with Pakistan. The significance of this four-chapter book lies in its departure from traditional Western-centric viewpoints, providing a distinct lens to comprehend the geopolitical and cultural strategies of these major Asian powers. This unique perspective on non-Western soft power will intrigue scholars, policymakers, and individuals interested in international relations.

Fuzzy Logic-Based Energy Management Strategy for Hybrid Fuel Cell Electric Ship Power and Propulsion System

The growing use of proton-exchange membrane fuel cells (PEMFCs) in hybrid propulsion systems is aimed at replacing traditional internal combustion engines and reducing greenhouse gas emissions. Effective power distribution between the fuel cell and the energy storage system (ESS) is crucial and has led to a growing emphasis on developing energy management systems (EMSs) to efficiently implement this integration. To address this goal, this study examines the performance of a fuzzy logic rule-based strategy for a hybrid fuel cell propulsion system in a small hydrogen-powered passenger vessel. The primary objective is to optimize fuel efficiency, with particular attention on reducing hydrogen consumption. The analysis is carried out under typical operating conditions encountered during a river trip. Comparisons between the proposed strategy with other approaches—control based, optimization based, and deterministic rule based—are conducted to verify the effectiveness of the proposed strategy. Simulation results indicated that the EMS based on fuzzy logic mechanisms was the most successful in reducing fuel consumption. The superior performance of this method stems from its ability to adaptively manage power distribution between the fuel cell and energy storage systems.

Educational Diplomacy of Islamic Republic of Iran as the Soft Power Strategy in the Middle East

Nowadays, many countries are trying to increase their soft power authority using the university communication facilities. Educational exchanges and the creation of university branches in different parts of the world, especially in countries where there are common cultural fields, give these countries the opportunity to interact with elites and students expand their influence. The university sector, as the most important and effective branch in creating the future of a country, will have a great impact on understanding and cultural alignment between nations.In this regard, one of the important regions that have a lot of common cultural identity with the Islamic Republic of Iran is the Middle East region. This article aims to answer the question of how the Islamic Republic of Iran can use its academic capabilities as the educational diplomacy in order to promote its position as soft power in the Middle East. Accordingly, Iran can use the cultural capacities, the Persian language, the common background of civilization and the capability of its higher education, especially in the field of university exchanges to empower its soft power authority in the region.

Start-Up and Fault-Ride-Through Strategy for Offshore Wind Power via DRU-HVDC Transmission System

The diode-rectifier unit (DRU)-based high-voltage direct current (HVDC) transmission system offers an economical solution for offshore wind power transmission. However, this approach requires offshore wind farms to establish a strong grid voltage. To meet this requirement while fulfilling the dynamic characteristics of the DRU, this paper proposes an advanced grid-forming (GFM) control strategy for offshore wind turbines connected to DRU-HVDC. The strategy incorporates a P-U controller and a Q-ω controller based on reactive power synchronization. Furthermore, a novel virtual power-based pre-synchronization method and an adaptive virtual impedance technique are integrated into the proposed GFM control to improve system performance during wind turbine (WT) integration and low-voltage ride-through (LVRT) scenarios. The virtual power-based pre-synchronization method reduces voltage spikes during the integration of new wind turbines, while the adaptive virtual impedance technique effectively suppresses fault currents during low-voltage faults, enabling faster recovery. Simulation results validate the effectiveness of the proposed GFM control strategy, demonstrating improved start-up and LVRT performance through the pre-synchronization and adaptive virtual impedance methods.

A wind farm control strategy for frequency regulation reserve: Optimize wake loss and frequency support capability

—With a high proportion of renewable energy, the issue of grid frequency fluctuations is becoming increasingly prominent. To tackle this challenge, wind farms can enhance frequency regulation response by increasing rotational kinetic energy through overspeed control. However, this approach may result in energy losses due to the wake effect. This paper proposes an optimized configuration strategy for wind farm frequency regulation reserve (FRR), utilizing pitch angle cooperative control to reduce wake losses. The objective is to explore the optimal configuration for maximizing wind energy utilization under FRR conditions. A genetic algorithm is used to find the optimal control parameters in the established FLORIS-based wind farm power reserve wake model, which involves rotor speed and pitch angle control, to maximize output power and rotational kinetic energy. Based on this, a lookup table is constructed to map wind conditions to the optimal control parameters for different FRR level. According to the reserve power schedule, optimization control is applied to the wind farm. Simulation results show that, compared to the traditional equal distribution strategy for FRR power, the proposed control strategy can enhance the total kinetic energy reserve of the wind farm by optimizing wake loss, thereby improving frequency support capability.

Investigation in improving the Cs-free negative hydrogen ion production with short-pulse low power in the afterglow of pulse-power-modulated plasma sources

Abstract Pulse plasma ion sources have been shown to be capable of achieving high negative hydrogen ion densities ( n H − ) or currents. The fast cooling of the electrons and reduction in the electron density (n e) provide favorable plasma conditions to improve the H− production, with a high density ratio of negative hydrogen ions to electrons during the pulse-off period. The purpose of this research is to further improve the performance of volume-produced H− ion sources based on the pulse power modulation. In this study, a time-modulated negative hydrogen plasma sustained by 10 kHz pulse power at the typical gas pressure of 0.3 Pa was numerically investigated using a global model. The model is compared with measurements obtained in a pulsed radio frequency ion source and shows a reasonable agreement. A steplike low-high power strategy in the active glow period and a short-pulse low power in part of the afterglow period are employed to mitigate overshoot of the electron temperature (T e) in the initial stage of the pulse period and to optimize H− production in the afterglow, respectively. The model predicts that a small-magnitude, short-duration low power operation in the afterglow increases n H − and decreases n e from the onset of the low power until the beginning of the next high power pulse, due to a modest temporary increase in the T e (less than 2 eV). It facilitates dissociative electron attachments and thus H− formation. The reduction in the n e indicates that positive ions lost to the walls cannot be compensated by weak ionization. H− production with a low number of co-extracted electrons can be optimized by adjusting the magnitude and duration of the low power in the afterglow.

5G Communication Network and Federated Learning for College Accounting Informatization Teaching

At present, the social economy is entering the information age represented by computer, communication technology and network technology as the core, and the continuous development of modern information technology will certainly have a great impact on the teaching mode, content and methods of traditional accounting computerization. We aim to improve the existing higher vocational accounting teaching mode by building a multi-integrated teaching mode through federated learning based on 5G communication network as an environment for efficient information transfer. In addition, we develop a joint optimization strategy for priority-dependent task offloading, wireless bandwidth, and computational power in a distributed machine learning approach to ensure that more resources are allocated to users with higher priority while protecting user data privacy and reducing learning overhead. We have conducted extensive simulation experiments for both environments, and these simulation results demonstrate the effectiveness of our proposed solutions for different problems from different perspectives.

Design strategies and systematic analysis of GaN vertical MPS diodes with T-shaped shielding rings

Abstract We report gallium nitride (GaN) vertical merged pn-Schottky (MPS) diodes with T-shaped p-GaN shielding rings (SRs). The embedded T-shaped SR features an overlapped depletion region by the lateral and vertical p n junctions under reverse bias condition, which can effectively enhance the charge coupling effect and homogenize the 2-D electric field distribution. In the meantime, the incorporation of the T-shaped SRs can minimize unnecessary depletion of the vertical conduction channel and guarantee a decent current spreading through the drift region. The impact of the key design parameters on the reverse breakdown and forward conduction performance are investigated systematically. We found that the doping concentration and the geomatical shape of the T-shaped p-GaN SRs are closed related to the electric field distribution and forward current conduction behavior, which determines the reverse breakdown and forward conduction performance. With optimum design parameters of the T-shaped SRs, the breakdown voltage of the MPS diodes features a dramatic improvement to 2749 V from 1123 V in conventional MPS diodes. The results can provide a design strategy for high performance vertical GaN power diodes towards high-power and high-frequency applications.

Lyapunov control strategy for low-frequency offshore wind power based on hexagonal converters

Lyapunov control strategy for low-frequency offshore wind power based on hexagonal converters

Symphonic music and cultural statecraft: the rise of symphonic statecraft in the post-Mao China

ABSTRACT Despite extensive studies on China’s soft power assets and strategies, the role of symphonic music within its cultural statecraft remains underexplored. This paper introduces the notion of ‘symphonic statecraft’ to examine the targeted and context-specific nature of China’s cultural efforts, focusing on how China adapts this globally recognized art form for its nation-building project. Using mixed methods, the study analyses awards from national composition contests between 1978 and 2012 and the programming choices of the China National Symphony Orchestra from 2006 to 2023 to reveal an environment shaped by selective state sponsorship that allows for artistic autonomy. The findings demonstrate a nuanced interplay between global influences and local interpretations, illustrating how China crafts narratives that interweave its enduring civilizational essence with contemporary aspirations. This evolving strategy absorbs increasingly diverse themes and moves beyond surface-level propaganda while maintaining strategic boundaries, reflecting the process of selective openness in China’s symphonic identity formation.

”It Looks Like a Spell…”: Acceptance of Crime Commission as Power Strategy in Confessional Statements in Police–Suspect Interactions in Ibadan, Southwestern Nigeria

ABSTRACT Studies on police-suspect interactions (PSIs) have largely foregrounded the institutional power exhibited by investigating police officers (IPOs) in the interactions, with most studies constructing suspects as powerless. This study, through a critical engagement of five purposively sampled cases (including rape, incest, attempted murder and being in possession of contraband) from the over 50 interactions and cases observed at the State Criminal Investigation Department, Iyaganku, Oyo State, Nigeria, reveals suspects orient towards aspects of shared socio-cultural norms among the Yoruba, in attempts to manipulate IPOs. In particular suspects allude to certain aspects of the Yoruba socio-cultural life and belief system, largely connected to the people’s socio-cultural understanding around peer and alcohol influence, spell casting, working one’s way to greatness and admit your ‘fault’ to shorten your punishment in order to overwhelm the socio-cognitive reasoning of IPOs.

Dissimilar laser welding of high-thickness Cu/Al plates for high-current density electrical batteries

Electrical batteries connecting is a crucial phase in the fabrication of electrical vehicles. It is usually performed using high-quality lasers focused on narrow spot, to overcome the low optical absorptivity of copper and/or aluminum and displaced with high-speed scanner to accomplish the production rate. In applications where the current density is high (naval, heavy transport, etc) the busbars used for the electrical connections are thick (0.8-1 mm) increasing the difficulties of having joints with no defects. In this paper, an in-depth analysis of the impact of laser power, welding speed, and innovative scanning strategy on joint quality is presented for lap welding of nickel-plated copper (0.8 mm) to AA1050 alloy (3 mm). Process optimization involves achieving the desired weld area while controlling metal-mixing indices to limit the formation of brittle intermetallic compounds, cracks and voids. Weld joint quality assessment, including metallographic examination, microhardness tests and SEM- EDX analysis is presented and discussed.

Commissioned Book Review: Md. Nazmul Islam, Power of Bonding and Non-Western Soft Power Strategy in Iran: Comparing China and India’s Engagement

Commissioned Book Review: Md. Nazmul Islam, <i>Power of Bonding and Non-Western Soft Power Strategy in Iran: Comparing China and India’s Engagement</i>

Network power and firm innovation: the moderating roles of power distance and procedural justice

PurposeThis study aims to investigate the influence of network power on exploratory and exploitative innovation and examines the moderating effects of power distance and procedural justice on these untested relationships.Design/methodology/approachThis study uses survey data collected from firms in China and explores the influential mechanisms of network power, power distance and procedural justice in firm innovation.FindingsThis study empirically shows that network power has an inverted U-shaped effect on exploratory and exploitative innovation. Power distance weakens the effect of network power on exploratory and exploitative innovation, and procedural justice enhances the effect of network power on exploratory and exploitative innovation.Research limitations/implicationsThis study extends resource dependence theory and contributes to the literature on innovation management. Future studies should use different collection channels or research methods to provide more evidence for model promotion. In addition, the dynamic power game among network members and the roles of other mediators or moderators warrant further consideration.Practical implicationsManagers should exercise power strategies properly and ensure that their innovation income exceeds expenditures. Managers need to pay serious attention to power distance and procedural justice in the network and formulate suitable cooperation strategies based on actual conditions.Originality/valueThis study applies the resource dependence theory to investigate the influence of network power on exploratory and exploitative innovation. In addition, the moderating roles of power distance and procedural justice in the above relationships, which have rarely been discussed in previous studies, were tested.