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A Cross-Multi-Domain Trust Assessment Authority Delegation Method Based on Automotive Industry Chain
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作者 Binyong Li Liangming Deng +1 位作者 Jie Zhang Xianhui Deng 《Computers, Materials & Continua》 SCIE EI 2025年第1期407-426,共20页
To solve the challenges of connecting and coordinating multiple platforms in the automotive industry and to enhance collaboration among different participants,this research focuses on addressing the complex supply rel... To solve the challenges of connecting and coordinating multiple platforms in the automotive industry and to enhance collaboration among different participants,this research focuses on addressing the complex supply relationships in the automotive market,improving data sharing and interactions across various platforms,and achieving more detailed integration of data and operations.We propose a trust evaluation permission delegation method based on the automotive industry chain.The proposed method combines smart contracts with trust evaluation mechanisms,dynamically calculating the trust value of users based on the historical behavior of the delegated entity,network environment,and other factors to avoid malicious node attacks during the permission delegation process.We also introduce strict control over the cross-domain permission granting and revocation mechanisms to manage the delegation path,prevent information leakage caused by malicious node interception,and effectively protect data integrity and privacy.Experimental analysis shows that this method meets the realtime requirements of collaborative interaction in the automotive industry chain and provides a feasible solution to permission delegation issues in the automotive industry chain,offering dynamic flexibility in authorization and scalability compared to most existing solutions. 展开更多
关键词 Automotive industry chain cross-domain access block chain delegate authority trust assessment
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Beyond the Lecture Hall:Rethinking Pedagogical Authority in the Age of AI and Hybrid Learning
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作者 XIAO Shufang 《Cultural and Religious Studies》 2025年第5期262-265,共4页
This essay critically re-examines pedagogical authority in the context of artificial intelligence(AI)and hybrid learning.As AI technologies disrupt the traditional teacher-centered model,and hybrid modalities challeng... This essay critically re-examines pedagogical authority in the context of artificial intelligence(AI)and hybrid learning.As AI technologies disrupt the traditional teacher-centered model,and hybrid modalities challenge spatial hierarchies,authority in education is increasingly dispersed and relational.The paper deconstructs historical structures of authority rooted in positional hierarchy and physical space,arguing instead for a model based on ethical mediation,dialogic engagement,and technological literacy.Educators must transform from content deliverers to facilitators of critical inquiry,guiding students through algorithmic complexity and fostering inclusive,participatory learning environments.By embracing relational authority and transparent practices,higher education can reclaim its democratic and transformative potential in the post-AI era. 展开更多
关键词 Pedagogical authority Artificial intelligence Hybrid learning Dialogic pedagogy
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Path analysis the influence of self-efficacy and professional identity on attitudes toward prescriptive authority among oncology nurse specialists
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作者 Cheng-Ping Qiao Bin Yang +3 位作者 Jiao Ma Qin Chen Xin-Ying He Xue Han 《World Journal of Clinical Oncology》 2025年第9期186-196,共11页
BACKGROUND Global tumor incidence rises and therapies advance,driving oncology nursing specialization.Granting nurses prescriptive authority optimizes care but polarizes nurses'attitudes due to factors like risk a... BACKGROUND Global tumor incidence rises and therapies advance,driving oncology nursing specialization.Granting nurses prescriptive authority optimizes care but polarizes nurses'attitudes due to factors like risk and competence,hindering policy implementation.AIM To investigate the current status of the attitudes of oncology specialist nurses toward having prescribing authority,specifically concerning symptom management and supportive care in oncology practice,and we conducted a path analysis of their influencing factors.METHODS As participants in the survey,oncology specialist nurses working in hospitals of different grades in Jiangsu Province were selected from March 2025 to May 2025 using a stratified sampling method.The questionnaires were administered using the general information questionnaire,the beliefs and attitudes about nurses'prescriptive authority scale,the nurses'professional identity scale,and the selfefficacy scale.Pearson’s method was used to analyze the correlation between beliefs and attitudes about the prescriptive authority,professional identity,and self-efficacy of nurses.Multiple linear regression was performed to analyze the factors influencing the beliefs and attitudes of nurses’prescriptive authority.The Amos plug-in was used to construct structural equation models to analyze the influencing pathways.RESULTS A total of 329 questionnaires were distributed,and 328 valid questionnaires were returned(effective recovery rate:99.70%).The total score of the 328 oncology nurses on the beliefs and attitudes about nurses'prescriptive authority scale was 101.88±15.13,indicating a moderately high level.Univariate analysis revealed that gender and hospital grade were associated with this score(P<0.05).The Pearson correlation analysis revealed that self-efficacy was positively correlated with the scores of the beliefs and attitudes about nurses’prescriptive authority scale and the nurses’professional identity scale(r=0.4999,P<0.0001 and r=0.7048,P<0.05,respectively),whereas occupational identity was positively correlated only with the former(r=0.6209,P<0.05).Multiple linear regression analysis revealed occupational identity and self-efficacy as the factors influencing the scores of the beliefs and attitudes about nurses’prescriptive authority scale(P<0.05).The results of the path analysis revealed that selfefficacy significantly positively affected nurses’occupational identity and their beliefs and attitudes about having prescriptive authority;occupational identity played a mediating role between the two,with a mediating effect accounting for 54.46% of the total effect,and the structural equation model was well-fitted.CONCLUSION Oncology nurses have more positive attitudes toward prescriptive authority.In addition,self-efficacy positively and indirectly affects nurses’attitudes toward prescriptive authority through the mediating effect of occupational identity.This can be used as a basis for clinical practice to take targeted measures to improve nurses’self-efficacy and occupational identity,thus creating favorable conditions for effectively implementing the policy of prescriptive authority. 展开更多
关键词 Oncology nurse specialists SELF-EFFICACY Professional identity Nurse prescribing authority ATTITUDES
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Cost effective technologies for long range microwave wireless power transmission
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作者 CHOI Joon-Min KIM Dae-Kwan +3 位作者 PARK Durk-Jong YI Sang-Hwa KIM Dong-Min KO Dae-Ho 《中国空间科学技术(中英文)》 北大核心 2026年第1期122-134,共13页
Space-Based Solar Power(SBSP) presents a promising solution for achieving carbon neutrality and Renewable Electricity 100%(RE100) goals by offering a stable and continuous energy supply. However, its commercialization... Space-Based Solar Power(SBSP) presents a promising solution for achieving carbon neutrality and Renewable Electricity 100%(RE100) goals by offering a stable and continuous energy supply. However, its commercialization faces significant obstacles due to the technical challenges of long-distance microwave Wireless Power Transmission(WPT) from geostationary orbit. Even ground-based kilometer-scale WPT experiments remain difficult because of limited testing infrastructure, high costs, and strict electromagnetic wave regulations. Since the 1975 NASA-Raytheon experiment, which successfully recovered 30 kW of power over 1.55 km, there has been little progress in extending the transmission distance or increasing the retrieved power. This study proposes a cost-effective methodology for conducting long-range WPT experiments in constrained environments by utilizing existing infrastructure. A deep space antenna operating at 2.08 GHz with an output power of 2.3 kW and a gain of 55.3 dBi was used as the transmitter. Two test configurations were implemented: a 1.81 km ground-to-air test using an aerostat to elevate the receiver and a 1.82 km ground-to-ground test using a ladder truck positioned on a plateau. The rectenna consists of a lightweight 3×3 patch antenna array(0.9 m × 0.9 m), accompanied by a steering device and LED indicators to verify power reception. The aerostat-based test achieved a power density of 154.6 mW/m2, which corresponds to approximately 6.2% of the theoretical maximum. The performance gap is primarily attributed to near-field interference, detuning of the patch antenna, rectifier mismatch, and alignment issues. These limitations are expected to be mitigated through improved patch antenna fabrication, a transition from GaN to GaAs rectifiers optimized for lower input power, and the implementation of an automated alignment system. With these enhancements, the recovered power is expected to improve by approximately four to five times. The results demonstrate a practical and scalable framework for long-range WPT experiments under constrained conditions and provide key insights for advancing SBSP technology. 展开更多
关键词 wireless power transmission space-based solar power deep space antenna DSP KDSA KARI RECTENNA AEROSTAT
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A Study on the Beliefs and Attitudes of Nurses in Yunnan Province Towards Nurse Prescriptive Authority
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作者 Yulin Lu Jian Chen +3 位作者 Ying Li Jun Yu Yanyu Chen Jiangyu Xue 《Journal of Clinical and Nursing Research》 2025年第1期194-202,共9页
Objective: To investigate the current beliefs and attitudes of nurses in Yunnan Province toward prescriptive authority, analyze the influencing factors, and provide evidence for future research and policy formulation ... Objective: To investigate the current beliefs and attitudes of nurses in Yunnan Province toward prescriptive authority, analyze the influencing factors, and provide evidence for future research and policy formulation to support the establishment of nurses’ prescriptive authority in China. Method: A cross-sectional survey was conducted among 937 nurses in Yunnan Province using the Beliefs and Attitudes Scale on Nurses’ Prescriptive Authority. The scale assessed four dimensions: perceived need, self-efficacy, perceived benefits, and perceived barriers. Multiple linear regression analysis was used to identify factors influencing the overall score and each dimension. Results: The total score of the Beliefs and Attitudes Scale was 89.17 ± 17.69, indicating a moderate level of awareness and positive attitude among nurses. The highest-scoring dimension was perceived benefits (34.94 ± 8.04), while the lowest was perceived barriers (15.23 ± 3.5). Age was identified as a significant factor influencing the overall score and self-efficacy dimension (P < 0.05). Years of practice influenced the perceived benefits dimension (P = 0.051), while gender, age, and professional title were key factors affecting the perceived barriers dimension (P < 0.05). Male nurses and senior nurses demonstrated more caution toward potential risks associated with prescriptive authority. Conclusion: Nurses in Yunnan Province exhibit moderate levels of belief in and attitudes toward prescriptive authority, with age being the most significant influencing factor. Tailored training programs, policy promotion, and practical guidance are recommended to enhance nurses’ understanding and support for prescriptive authority, thereby improving nursing practices and addressing regional healthcare challenges. 展开更多
关键词 Nurses’prescriptive authority Beliefs and attitudes Influencing factors Yunnan Province Nursing policy
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A Learning-Based Passive Resilient Controller for Cyber-Physical Systems:Countering Stealthy Deception Attacks and Complete Loss of Actuators Control Authority
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作者 Liang Xin Zhi-Qiang Long 《IEEE/CAA Journal of Automatica Sinica》 2025年第7期1368-1380,共13页
Cyber-physical systems(CPSs)are increasingly vulnerable to cyber-attacks due to their integral connection between cyberspace and the physical world,which is augmented by Internet connectivity.This vulnerability necess... Cyber-physical systems(CPSs)are increasingly vulnerable to cyber-attacks due to their integral connection between cyberspace and the physical world,which is augmented by Internet connectivity.This vulnerability necessitates a heightened focus on developing resilient control mechanisms for CPSs.However,current observer-based active compensation resilient controllers exhibit poor performance against stealthy deception attacks(SDAs)due to the difficulty in accurately reconstructing system states because of the stealthy nature of these attacks.Moreover,some non-active compensation approaches are insufficient when there is a complete loss of actuator control authority.To address these issues,we introduce a novel learning-based passive resilient controller(LPRC).Our approach,unlike observer-based state reconstruction,shows enhanced effectiveness in countering SDAs.We developed a safety state set,represented by an ellipsoid,to ensure CPS stability under SDA conditions,maintaining system trajectories within this set.Additionally,by employing deep reinforcement learning(DRL),the LPRC acquires the capacity to adapt and diverse evolving attack strategies.To empirically substantiate our methodology,various attack methods were compared with current passive and active compensation resilient control methods to evaluate their performance. 展开更多
关键词 Actuator authority cyber-physical systems(CPSs) deep reinforcement learning(DRL) learning-based controller resilient control stealthy deception attacks(SDAs)
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Optimal Dispatch of Urban Distribution Networks Considering Virtual Power Plant Coordination under Extreme Scenarios
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作者 Yong Li Yuxuan Chen +4 位作者 Jiahui He Guowei He Chenxi Dai Jingjing Tong Wenting Lei 《Energy Engineering》 2026年第1期204-220,共17页
Ensuring reliable power supply in urban distribution networks is a complex and critical task.To address the increased demand during extreme scenarios,this paper proposes an optimal dispatch strategy that considers the... Ensuring reliable power supply in urban distribution networks is a complex and critical task.To address the increased demand during extreme scenarios,this paper proposes an optimal dispatch strategy that considers the coordination with virtual power plants(VPPs).The proposed strategy improves systemflexibility and responsiveness by optimizing the power adjustment of flexible resources.In the proposed strategy,theGaussian Process Regression(GPR)is firstly employed to determine the adjustable range of aggregated power within the VPP,facilitating an assessment of its potential contribution to power supply support.Then,an optimal dispatch model based on a leader-follower game is developed to maximize the benefits of the VPP and flexible resources while guaranteeing the power balance at the same time.To solve the proposed optimal dispatch model efficiently,the constraints of the problem are reformulated and resolved using the Karush-Kuhn-Tucker(KKT)optimality conditions and linear programming duality theorem.The effectiveness of the strategy is illustrated through a detailed case study. 展开更多
关键词 Urban distribution network virtual power plant power supply support leader-follower optimization game extreme weather scenarios
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Adaptive Grid-Interface Control for Power Coordination in Multi-Microgrid Energy Networks
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作者 Sk.A.Shezan 《Energy Engineering》 2026年第1期91-114,共24页
Modern power systems increasingly depend on interconnected microgrids to enhance reliability and renewable energy utilization.However,the high penetration of intermittent renewable sources often causes frequency devia... Modern power systems increasingly depend on interconnected microgrids to enhance reliability and renewable energy utilization.However,the high penetration of intermittent renewable sources often causes frequency deviations,voltage fluctuations,and poor reactive power coordination,posing serious challenges to grid stability.Conventional Interconnection FlowControllers(IFCs)primarily regulate active power flowand fail to effectively handle dynamic frequency variations or reactive power sharing in multi-microgrid networks.To overcome these limitations,this study proposes an enhanced Interconnection Flow Controller(e-IFC)that integrates frequency response balancing and an Interconnection Reactive Power Flow Controller(IRFC)within a unified adaptive control structure.The proposed e-IFC is implemented and analyzed in DIgSILENT PowerFactory to evaluate its performance under various grid disturbances,including frequency drops,load changes,and reactive power fluctuations.Simulation results reveal that the e-IFC achieves 27.4% higher active power sharing accuracy,19.6% lower reactive power deviation,and 18.2% improved frequency stability compared to the conventional IFC.The adaptive controller ensures seamless transitions between grid-connected and islanded modes and maintains stable operation even under communication delays and data noise.Overall,the proposed e-IFCsignificantly enhances active-reactive power coordination and dynamic stability in renewable-integrated multi-microgrid systems.Future research will focus on coupling the e-IFC with tertiary-level optimization frameworks and conducting hardware-in-the-loop validation to enable its application in large-scale smart microgrid environments. 展开更多
关键词 Active power flow control interconnection flow controller(IFC) frequency response micro grid stability reactive power management
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Instructions for Authors
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《International Journal of Minerals,Metallurgy and Materials》 2026年第1期F0002-F0002,共1页
International Journal of Minerals,Metallurgy and Materials is dedicated to the publication and the dissemination of original research articles (and occasional invited reviews) in the fields of Minerals,Metallurgy and ... International Journal of Minerals,Metallurgy and Materials is dedicated to the publication and the dissemination of original research articles (and occasional invited reviews) in the fields of Minerals,Metallurgy and Materials.It is covered by EI Compendex,SCI Expanded,Chemical Abstract,etc.Manuscript preparation The following components are required for a complete manuscript:Title,Author(s),Author affiliation(s),Abstract,Keywords,Main text,Acknowledgements and References. 展开更多
关键词 METALLURGY MINERALS research articles materials ei compendexsci complete manuscript titleauthor s author REVIEWS
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Equivalent Modeling with Passive Filter Parameter Clustering for Photovoltaic Power Stations Based on a Particle Swarm Optimization K-Means Algorithm
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作者 Binjiang Hu Yihua Zhu +3 位作者 Liang Tu Zun Ma Xian Meng Kewei Xu 《Energy Engineering》 2026年第1期431-459,共29页
This paper proposes an equivalent modeling method for photovoltaic(PV)power stations via a particle swarm optimization(PSO)K-means clustering(KMC)algorithm with passive filter parameter clustering to address the compl... This paper proposes an equivalent modeling method for photovoltaic(PV)power stations via a particle swarm optimization(PSO)K-means clustering(KMC)algorithm with passive filter parameter clustering to address the complexities,simulation time cost and convergence problems of detailed PV power station models.First,the amplitude–frequency curves of different filter parameters are analyzed.Based on the results,a grouping parameter set for characterizing the external filter characteristics is established.These parameters are further defined as clustering parameters.A single PV inverter model is then established as a prerequisite foundation.The proposed equivalent method combines the global search capability of PSO with the rapid convergence of KMC,effectively overcoming the tendency of KMC to become trapped in local optima.This approach enhances both clustering accuracy and numerical stability when determining equivalence for PV inverter units.Using the proposed clustering method,both a detailed PV power station model and an equivalent model are developed and compared.Simulation and hardwarein-loop(HIL)results based on the equivalent model verify that the equivalent method accurately represents the dynamic characteristics of PVpower stations and adapts well to different operating conditions.The proposed equivalent modeling method provides an effective analysis tool for future renewable energy integration research. 展开更多
关键词 Photovoltaic power station multi-machine equivalentmodeling particle swarmoptimization K-means clustering algorithm
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Anomaly Detection Method of Power Internet of Things Terminals in Zero-Trust Environment
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作者 Sun Pengzhan Ren Yinlin +2 位作者 Shao Sujie Yang Chao Qiu Xuesong 《China Communications》 2026年第1期290-305,共16页
With more and more IoT terminals being deployed in various power grid business scenarios,terminal reliability has become a practical challenge that threatens the current security protection architecture.Most IoT termi... With more and more IoT terminals being deployed in various power grid business scenarios,terminal reliability has become a practical challenge that threatens the current security protection architecture.Most IoT terminals have security risks and vulnerabilities,and limited resources make it impossible to deploy costly security protection methods on the terminal.In order to cope with these problems,this paper proposes a lightweight trust evaluation model TCL,which combines three network models,TCN,CNN,and LSTM,with stronger feature extraction capability and can score the reliability of the device by periodically analyzing the traffic behavior and activity logs generated by the terminal device,and the trust evaluation of the terminal’s continuous behavior can be achieved by combining the scores of different periods.After experiments,it is proved that TCL can effectively use the traffic behaviors and activity logs of terminal devices for trust evaluation and achieves F1-score of 95.763,94.456,99.923,and 99.195 on HDFS,BGL,N-BaIoT,and KDD99 datasets,respectively,and the size of TCL is only 91KB,which can achieve similar or better performance than CNN-LSTM,RobustLog and other methods with less computational resources and storage space. 展开更多
关键词 anomaly detection distributed machine learning power internet of Things zero trust
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Dynamic Boundary Optimization via IDBO-VMD:A Novel Power Allocation Strategy for Hybrid Energy Storage with Enhanced Grid Stability
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作者 Zujun Ding Qi Xiang +10 位作者 Chengyi Li Mengyu Ma Chutong Zhang Xinfa Gu Jiaming Shi Hui Huang Aoyun Xia Wenjie Wang Wan Chen Ziluo Yu Jie Ji 《Energy Engineering》 2026年第1期527-552,共26页
In order to address environmental pollution and resource depletion caused by traditional power generation,this paper proposes an adaptive iterative dynamic-balance optimization algorithm that integrates the Improved D... In order to address environmental pollution and resource depletion caused by traditional power generation,this paper proposes an adaptive iterative dynamic-balance optimization algorithm that integrates the Improved Dung Beetle Optimizer(IDBO)with VariationalMode Decomposition(VMD).The IDBO-VMD method is designed to enhance the accuracy and efficiency of wind-speed time-series decomposition and to effectively smooth photovoltaic power fluctuations.This study innovatively improves the traditional variational mode decomposition(VMD)algorithm,and significantly improves the accuracy and adaptive ability of signal decomposition by IDBO selfoptimization of key parameters K and a.On this basis,Fourier transform technology is used to define the boundary point between high frequency and low frequency signals,and a targeted energy distribution strategy is proposed:high frequency fluctuations are allocated to supercapacitors to quickly respond to transient power fluctuations;Lowfrequency components are distributed to lead-carbon batteries,optimizing long-term energy storage and scheduling efficiency.This strategy effectively improves the response speed and stability of the energy storage system.The experimental results demonstrate that the IDBO-VMD algorithm markedly outperforms traditional methods in both decomposition accuracy and computational efficiency.Specifically,it effectively reduces the charge–discharge frequency of the battery,prolongs battery life,and optimizes the operating ranges of the state-of-charge(SOC)for both leadcarbon batteries and supercapacitors.In addition,the energy management strategy based on the algorithm not only improves the overall energy utilization efficiency of the system,but also shows excellent performance in the dynamic management and intelligent scheduling of renewable energy generation. 展开更多
关键词 Energy efficiency hybrid energy storage system intelligent algorithm power fluctuation mitigation renewable energy
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Optimal Operation of Virtual Power Plants Based on Revenue Distribution and Risk Contribution
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作者 Heping Qi Wenyao Sun +2 位作者 Yi Zhao Xiaoyi Qian Xingyu Jiang 《Energy Engineering》 2026年第1期373-392,共20页
Virtual power plant(VPP)integrates a variety of distributed renewable energy and energy storage to participate in electricity market transactions,promote the consumption of renewable energy,and improve economic effici... Virtual power plant(VPP)integrates a variety of distributed renewable energy and energy storage to participate in electricity market transactions,promote the consumption of renewable energy,and improve economic efficiency.In this paper,aiming at the uncertainty of distributed wind power and photovoltaic output,considering the coupling relationship between power,carbon trading,and green cardmarket,the optimal operationmodel and bidding scheme of VPP in spot market,carbon trading market,and green card market are established.On this basis,through the Shapley value and independent risk contribution theory in cooperative game theory,the quantitative analysis of the total income and risk contribution of various distributed resources in the virtual power plant is realized.Moreover,the scheduling strategies of virtual power plants under different risk preferences are systematically compared,and the feasibility and accuracy of the combination of Shapley value and independent risk contribution theory in ensuring fair income distribution and reasonable risk assessment are emphasized.A comprehensive solution for virtual power plants in the multi-market environment is constructed,which integrates operation strategy,income distribution mechanism,and risk control system into a unified analysis framework.Through the simulation of multi-scenario examples,the CPLEXsolver inMATLAB software is used to optimize themodel.The proposed joint optimization scheme can increase the profit of VPP participating in carbon trading and green certificate market by 29%.The total revenue of distributed resources managed by VPP is 9%higher than that of individual participation. 展开更多
关键词 Virtual power plant carbon trading green certificate trading CVAR shapley risk contribution optimal scheduling
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The Electric Wave:Battery-powered vessels and smart systems are directing China’s rivers towards a sustainable future
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作者 GE LIJUN 《ChinAfrica》 2026年第2期49-51,共3页
Each morning at Yangluo Port in Wuhan,Hubei Province,the all-electric cargo vessel Huahang Xinneng No.1 completes a battery swap in under 10 minutes before returning to service with nearly 8,000 kWh of power onboard。
关键词 yangluo port china WUHAN battery swap battery powered vessels sustainable future smart systems electric waves
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The Diplomatic Power of Proverbs--Xi Jinping’s African discourse harmonises Chinese and African wisdom and boosts the construction of a China-Africa community with a shared future
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作者 ETIENNE BANKUWIHA 《ChinAfrica》 2026年第1期23-25,共3页
As a Burundian doctoral student at Nanjing University,my personal journey is closely intertwined with China’s development in the new era and the deepening China-Africa partnership.Recently,my experiences have given m... As a Burundian doctoral student at Nanjing University,my personal journey is closely intertwined with China’s development in the new era and the deepening China-Africa partnership.Recently,my experiences have given me a deeper appreciation of the importance of people-to-people exchanges between China and Africa. 展开更多
关键词 shared future china africa community diplomatic power african wisdom african discourse chinese wisdom proverbs xi jinping
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Phase field model of fracture propagation and pressure evolution induced by fluid injection considering the effect of initial stress field in power generation test project of Gonghe Basin,China
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作者 Hong-wei Wang Hai-dong Wu +4 位作者 He-juan Liu Yong-bo Tie Li-sha Hu Lin-you Zhang Xian-peng Jin 《China Geology》 2026年第1期25-43,共19页
Hydraulic stimulation technology is widely employed to enhance the permeability of geothermal reservoirs.Nevertheless,accurately predicting hydraulic fracture propagation in complex geological conditions remains chall... Hydraulic stimulation technology is widely employed to enhance the permeability of geothermal reservoirs.Nevertheless,accurately predicting hydraulic fracture propagation in complex geological conditions remains challenging,thereby hindering the effective utilization of existing natural fractures.In this study,a phase field model was developed utilizing the finite element method to examine the influence of fluid presence,stress conditions,and natural fractures on the initiation and propagation of hydraulic fractures.The model employs Biot's poroelasticity theory to establish the coupling between the displacement field and the fluid field,while the phase field theory is applied to simulate fracture behavior.The results show that whenσ_(x0)/σ_(y0)<3 or qf<20 kg/(m^(3)·s),the presence of natural fractures can alter the original propagation direction of hydraulic fractures.Conversely,in the absence of these conditions,the propagation path of natural fractures is predominantly influenced by the initial stress field.Furthermore,based on the analysis of breakdown pressure and damage area,the optimal intersection angle between natural fractures and hydraulic fractures is determined to range from 45°to 60°.Finally,once a dominant channel forms,initiating and propagating hydraulic fractures in other directions becomes increasingly difficult,even in highly fractured areas.This method tackles the challenges of initiating and propagating hydraulic fractures in complex geological conditions,providing a theoretical basis for optimizing Enhanced Geothermal System(EGS)projects. 展开更多
关键词 Hot dry rock permeability Enhance geothermal system(EGS) Hydraulic stimulation Phase field model Fracture propagation Breakdown pressure power generation test Clean energy geological survey engineering
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Construction of MMC-CLCC Hybrid DC Transmission System and Its Power Flow Reversal Control Strategy
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作者 Yechun Xin Xinyuan Zhao +3 位作者 Dong Ding Shuyu Chen Chuanjie Wang Tuo Wang 《Energy Engineering》 2026年第1期460-474,共15页
To enhance power flow regulation in scenarios involving large-scale renewable energy transmission via high-voltage direct current(HVDC)links and multi-infeed DC systems in load-center regions,this paper proposes a hyb... To enhance power flow regulation in scenarios involving large-scale renewable energy transmission via high-voltage direct current(HVDC)links and multi-infeed DC systems in load-center regions,this paper proposes a hybrid modular multilevel converter–capacitor-commutated line-commutated converter(MMC-CLCC)HVDC transmission system and its corresponding control strategy.First,the system topology is constructed,and a submodule configuration method for the MMC—combining full-bridge submodules(FBSMs)and half-bridge submodules(HBSMs)—is proposed to enable direct power flow reversal.Second,a hierarchical control strategy is introduced,includingMMCvoltage control,CLCC current control,and a coordinationmechanism,along with the derivation of the hybrid system’s power flow reversal characteristics.Third,leveraging the CLCC’s fast current regulation and theMMC’s negative voltage control capability,a coordinated power flow reversal control strategy is developed.Finally,an 800 kV MMC-CLCC hybrid HVDC system is modeled in PSCAD/EMTDC to validate the power flow reversal performance under a high proportion of full-bridge submodule configuration.Results demonstrate that the proposed control strategy enables rapid(1-s transition)and smooth switching of bidirectional power flow without modifying the structure of primary equipment:the transient fluctuation ofDC voltage from the rated value(UdcN)to themaximumreverse voltage(-kUdcN)is less than 5%;the DC current strictly follows the preset characteristic curve with a deviation of≤3%;the active power reverses continuously,and the system maintains stable operation throughout the reversal process. 展开更多
关键词 Hybrid HVDC transmission modular multilevel converter(MMC) controllable line commutated converter(CLCC) online power flow reversal full-bridge and half-bridge submodules new energy through dc transmission system
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基于IPowerICA的轨道车辆轮对轴承故障诊断
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作者 刘婷 郑瑞防 +2 位作者 李艳娇 王海瑞 李克铭 《制造业自动化》 2026年第1期33-40,共8页
针对轨道车辆轮对轴承故障检测问题,提出一种改进幂迭代快速独立成分分析方法。该方法首先利用能量幅值希尔伯特变换对轮对轴承故障信号进行降噪处理;继而应用最大加权迭代分解手段重构降噪信号的预白化向量;随后,在预白化向量引导下进... 针对轨道车辆轮对轴承故障检测问题,提出一种改进幂迭代快速独立成分分析方法。该方法首先利用能量幅值希尔伯特变换对轮对轴承故障信号进行降噪处理;继而应用最大加权迭代分解手段重构降噪信号的预白化向量;随后,在预白化向量引导下进行幂迭代快速独立成分分析并根据最小等级注意熵选择最优分离结果;对比理论故障特征频率及最优分离结果的包络谱中突出频率成分,判断轮对轴承是否发生故障。实验数据分析结果表明,所提方法能从复杂轮对轴承原始信号中判别微弱特征信息,高效判定轮对轴承损伤与否,为实际工程应用提供参考价值。 展开更多
关键词 轮对轴承 故障诊断 能量幅值希尔伯特变换 最大加权迭代分解与重构 powerICA
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The eligibility criteria,training content,and scope of practice for prescriptive authority for midwives:a modified Delphi study 被引量:3
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作者 Shi-Fan Han Hong-Xia Ren +2 位作者 Xiu-Juan Wang Xiao-Ding Yue Si-Yu Dou 《Frontiers of Nursing》 CAS 2019年第3期191-201,共11页
Objective:To investigate the necessary eligibility criteria for prescriptive authority for midwives,gather suggestions from experts on training content for prescriptive authority for midwives,and explore the scope of ... Objective:To investigate the necessary eligibility criteria for prescriptive authority for midwives,gather suggestions from experts on training content for prescriptive authority for midwives,and explore the scope of practice of their prescriptive authority in certain circumstances.The results of this study could serve as a reference for the development of policies on prescriptive authority for midwives.Methods:Based on a literature search and semistructured interviews,a modified Delphi method was first used to conduct 2 rounds of expert consultation on eligibility criteria and training content for prescriptive authority for midwives.This stage included nursing experts(20)and medical experts(16)engaged in midwifery in many tertiary Grade A hospitals in China.Subsequently,consultation on the scope of practice of prescriptive authority for midwives was conducted with nursing experts(18)and medical experts(14)engaged in midwifery in many tertiary Grade A hospitals in China.The suggestions from the experts were analyzed using statistical methods to confirm the eligibility criteria for prescriptive authority,training content,circumstances,scope of practice for prescriptive authority,and the prescription forms.Results:Among the consulted experts,70.59%(the highest acceptance rate)considered an undergraduate degree to be the minimum educational requirement for midwives to be eligible for prescriptive authority,85.29%(the highest acceptance rate)considered the supervisor nurse to be the minimum technical position experience necessary for midwives to be eligible for having prescriptive authority,and 50%(the highest acceptance rate)considered 5 years to be the minimum number of years of experience in the specialty for midwives to be eligible for prescriptive authority.The applicants should at least be practicing at Grade C hospitals,which was the consensus among 91.18%of the consulted experts.Among the consulted experts,100%,100%,97.06%,94.12%,and 94.12%agreed that the applicants should have knowledge in pharmacology,laws and ethics,nursing,diagnostics,and midwifery,respectively.The consulted experts confirmed 22 related course topics and identified 6 specific circumstances in which the midwives could partially practice prescriptive authority,including uterine atony,excessive uterine contraction,postpartum hemorrhage,premature rupture of fetal membranes,normal labor,and neonatal asphyxia.Under these 6 circumstances,the consulted experts commonly agreed that there were 20 medication prescriptions and 13 auxiliary examination prescriptions that could be prescribed by midwives.Of these prescriptions,51.5%were independent prescriptions,30.3%were protocol prescriptions,and the remaining 18.2%were both independent and protocol prescriptions.Conclusions:Midwives who have an undergraduate degree,supervisor nurse position,and 5 years of practice in Grade C hospitals are considered eligible to apply for prescriptive authority.Partial prescriptive authority could be granted after regulated training in fundamental theories and practices,which could improve the independence and professionalism of midwifery. 展开更多
关键词 Delphi study MIDWIFE ELIGIBILITY criteria training content circumstances SCOPE of practice prescriptive authority PRESCRIPTION forms
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移动通信企业双向收费Authority-hub客户排序算法
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作者 金海燕 宫雨 武森 《计算机应用》 CSCD 北大核心 2005年第B12期190-192,共3页
电信移动通话与网页分级问题有相似之处,都是通过连通(通话或链接)加强双方联系的重要程度。由此,受网页分级问题搜索引擎算法HITS(Hyperlink-Induced Topic Search)算法的启发,针对目前移动通信企业双向收费的现实,本文提出了双向收费A... 电信移动通话与网页分级问题有相似之处,都是通过连通(通话或链接)加强双方联系的重要程度。由此,受网页分级问题搜索引擎算法HITS(Hyperlink-Induced Topic Search)算法的启发,针对目前移动通信企业双向收费的现实,本文提出了双向收费Authority-hub客户排序算法。与其他客户分析方法相比,该算法对客户按价值进行排序时,不仅考虑了客户自身,而且考虑了客户之间的相互影响。 展开更多
关键词 HITS 客户分析 authority—hub
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