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Online Optimization to Suppress the Grid-Injected Power Deviation of Wind Farms with Battery-Hydrogen Hybrid Energy Storage Systems 被引量:1
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作者 Min Liu Qiliang Wu +4 位作者 Zhixin Li Bo Zhao Leiqi Zhang Junhui Li Xingxu Zhu 《Energy Engineering》 2025年第4期1403-1424,共22页
To address the issue of coordinated control of multiple hydrogen and battery storage units to suppress the grid-injected power deviation of wind farms,an online optimization strategy for Battery-hydrogen hybrid energy... To address the issue of coordinated control of multiple hydrogen and battery storage units to suppress the grid-injected power deviation of wind farms,an online optimization strategy for Battery-hydrogen hybrid energy storage systems based on measurement feedback is proposed.First,considering the high charge/discharge losses of hydrogen storage and the low energy density of battery storage,an operational optimization objective is established to enable adaptive energy adjustment in the Battery-hydrogen hybrid energy storage system.Next,an online optimization model minimizing the operational cost of the hybrid system is constructed to suppress grid-injected power deviations with satisfying the operational constraints of hydrogen storage and batteries.Finally,utilizing the online measurement of the energy states of hydrogen storage and batteries,an online optimization strategy based on measurement feedback is designed.Case study results show:before and after smoothing the fluctuations in wind power,the time when the power exceeded the upper and lower limits of the grid-injected power accounted for 24.1%and 1.45%of the total time,respectively,the proposed strategy can effectively keep the grid-injected power deviations of wind farms within the allowable range.Hydrogen storage and batteries respectively undertake long-term and short-term charge/discharge tasks,effectively reducing charge/discharge losses of the Battery-hydrogen hybrid energy storage systems and improving its operational efficiency. 展开更多
关键词 Battery-hydrogen hybrid energy storage systems grid-injected power deviations measurement feedback online optimization energy states
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A Verifiable Trust-Based CP-ABE Access Control Scheme for Cloud-Assisted Renewable Energy Systems
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作者 Jiyu Zhang Kehe Wu +4 位作者 Ruomeng Yan Zheng Tian Yizhen Sun Yuxi Wu Yaogong Guo 《Computers, Materials & Continua》 SCIE EI 2025年第1期1211-1232,共22页
Renewable Energy Systems(RES)provide a sustainable solution to climate warming and environmental pollution by enhancing stability and reliability through status acquisition and analysis on cloud platforms and intellig... Renewable Energy Systems(RES)provide a sustainable solution to climate warming and environmental pollution by enhancing stability and reliability through status acquisition and analysis on cloud platforms and intelligent processing on edge servers(ES).However,securely distributing encrypted data stored in the cloud to terminals that meet decryption requirements has become a prominent research topic.Additionally,managing attributes,including addition,deletion,and modification,is a crucial issue in the access control scheme for RES.To address these security concerns,a trust-based ciphertext-policy attribute-based encryption(CP-ABE)device access control scheme is proposed for RES(TB-CP-ABE).This scheme effectivelymanages the distribution and control of encrypted data on the cloud through robust attribute key management.By introducing trust management mechanisms and outsourced decryption technology,the ES system can effectively assess and manage the trust worthiness of terminal devices,ensuring that only trusted devices can participate in data exchange and access sensitive information.Besides,the ES system dynamically evaluates trust scores to set decryption trust thresholds,thereby regulating device data access permissions and enhancing the system’s security.To validate the security of the proposed TB-CP-ABE against chosen plaintext attacks,a comprehensive formal security analysis is conducted using the widely accepted random oraclemodel under the decisional q-Bilinear Diffie-Hellman Exponent(q-BDHE)assumption.Finally,comparative analysis with other schemes demonstrates that the TB-CP-ABE scheme cuts energy/communication costs by 43%,and scaleswell with rising terminals,maintaining average latency below 50ms,ensuring real-time service feasibility.The proposed scheme not only provides newinsights for the secure management of RES but also lays a foundation for future secure energy solutions. 展开更多
关键词 Access control renewable energy systems(RES) ciphertext-policy attribute-based encryption(CP-ABE) security
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Multi-Factor Authentication for Keyless Entry Systems: An Innovative Approach to Automotive Security
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作者 Danilo Brito Shakour Abuzneid 《Journal of Information Security》 2025年第1期78-100,共23页
Car manufacturers aim to enhance the use of two-factor authentication (2FA) to protect keyless entry systems in contemporary cars. Despite providing significant ease for users, keyless entry systems have become more s... Car manufacturers aim to enhance the use of two-factor authentication (2FA) to protect keyless entry systems in contemporary cars. Despite providing significant ease for users, keyless entry systems have become more susceptible to appealing attacks like relay attacks and critical fob hacking. These weaknesses present considerable security threats, resulting in unauthorized entry and car theft. The suggested approach combines a conventional keyless entry feature with an extra security measure. Implementing multi-factor authentication significantly improves the security of systems that allow keyless entry by reducing the likelihood of unauthorized access. Research shows that the benefits of using two-factor authentication, such as a substantial increase in security, far outweigh any minor drawbacks. 展开更多
关键词 MFA Keyless Entry systems Automotive Security Biometric Authentication
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A Systematic Review of the DeLone&McLean Model in Enterprise Resource Planning(ERP)Systems Success
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作者 Niel Agrisman Barus Iskandar Muda Sambas Ade Kesuma 《Journal of Modern Accounting and Auditing》 2025年第3期90-107,共18页
Enterprise Resource Planning(ERP)systems play a pivotal role in modern organizations by integrating business processes,enhancing operational efficiency,and supporting decision-making.Evaluating the success of ERP impl... Enterprise Resource Planning(ERP)systems play a pivotal role in modern organizations by integrating business processes,enhancing operational efficiency,and supporting decision-making.Evaluating the success of ERP implementations remains a critical challenge for both researchers and practitioners.The DeLone&McLean(D&M)Information Systems(IS)Success Model has been widely adopted as a theoretical framework to assess ERP success,yet its application in dynamic and evolving technological landscapes requires further examination.This systematic review synthesizes empirical studies from 2017 to 2024 that apply the D&M Model to evaluate ERP system success.The study aims to:(1)identify key trends in the application of the D&M Model across different organizational and technological contexts,(2)analyze the most influential success factors-system quality,information quality,service quality,user satisfaction,use,and net benefits-and their interrelationships,and(3)highlight emerging challenges and opportunities for refining the model in ERP research.Findings reveal that while the D&M Model provides a robust foundation for assessing ERP success,contextual factors such as organizational climate,leadership support,and mandatory vs.voluntary usage significantly influence outcomes.Additionally,advancements in digital transformation,AI,and cloud-based ERP systems introduce new dimensions that the traditional model may not fully capture.The review also identifies gaps in longitudinal studies and cross-cultural validations of the D&M Model in ERP settings.Based on the analysis,this paper proposes an enhanced framework that integrates dynamic moderators and post-implementation metrics to better align the D&M Model with contemporary ERP environments.The study contributes to IS literature by offering a comprehensive evaluation of the D&M Model’s applicability and limitations in ERP research,while providing actionable insights for organizations seeking to optimize ERP success. 展开更多
关键词 DeLone&McLean model ERP success information systems systematic review organizational performance digital transformation
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Effectiveness of various chemical leaching systems in the remediation of chromium-contaminated soil and their impact on chromium speciation
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作者 Yuxiao Jiang Chao Hu +3 位作者 Aoyu Zhou Huiyang Qiu Benyi Cao Jian Xu 《Journal of Environmental Sciences》 2025年第11期77-89,共13页
Chemical leaching techniques have been proven effective in removing heavymetal contaminants fromsoil using various leaching agents.Previous research has shown that both singleagent and composite leaching systems have ... Chemical leaching techniques have been proven effective in removing heavymetal contaminants fromsoil using various leaching agents.Previous research has shown that both singleagent and composite leaching systems have been applied for the remediation of chromiumcontaminated soils,with varying degrees of success depending on soil type and contaminant form.However,the removal rate of total chromium(Cr)and hexavalent chromium(Cr(Ⅵ))often fluctuates based on the chemical composition of the leaching agents,as well as the soil’s physicochemical properties,such as pH and Cr speciation stability.Therefore,this study investigates the effectiveness of 20 composite leaching systems,including deionized water,lime water,calcium chloride,sodium carbonate,and sodium phosphate,through soil column leaching tests.The aim was to evaluate their impact on soil pH,total Cr,and Cr(Ⅵ)removal,and to examine the transformation of various Cr species during the leaching process.Results reveal that lime water and sodium phosphate were particularly effective in stabilizing Cr(Ⅵ)and neutralizing soil pH,while total Cr removal amount ranged from 197.4 mg/kg to 1671.6 mg/kg and Cr(Ⅵ)removal amount ranged from 113.2mg/kg to 316.8mg/kg.We also find that using 0.2 mol/L citric acid,0.1 mol/L hydrochloric acid,and 1.2 mL/g lime solution adjusted soil pH to 7.37,with average removal efficiencies of 34.6%.for total Cr and 72.7%for Cr(Ⅵ).Overall,our results suggest that the combined use of lime water and sodium phosphate is an effective strategy for remediating chromium-contaminated soil,particularly for stabilizing unleached Cr and adjusting soil pH. 展开更多
关键词 Chemical leaching techniques Metal contaminants REMEDIATION Removal rate Total chromium Leaching systems
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Ecological Security Assessment and Risk Management Framework for Recycled Water Systems in Landscape Hydration
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作者 Xinmiao Wang 《Journal of Architectural Research and Development》 2025年第2期28-31,共4页
Against the backdrop of intensifying global water scarcity,reclaimed water reuse has emerged as a critical strategy for ecological replenishment of landscape water bodies.However,its potential ecological risks remain ... Against the backdrop of intensifying global water scarcity,reclaimed water reuse has emerged as a critical strategy for ecological replenishment of landscape water bodies.However,its potential ecological risks remain underexplored.This study aims to establish a multidimensional ecological safety evaluation framework for reclaimed water replenishment systems and propose hierarchical risk prevention strategies.By integrating ecotoxicological assays(algae growth inhibition,Daphnia behavioral anomalies,zebrafish embryo toxicity),multimedia exposure modeling,and Monte Carlo probabilistic simulations,the risk contributions and spatial heterogeneity of typical pollutants are quantitatively analyzed.Results revealed that sulfamethoxazole(RQ=2.3)and diclofenac(RQ=1.8)posed high ecological risks,with their effects nonlinearly correlated with hydraulic retention time(HRT<3 days)and nutrient loading(TN>1.2 mg/L).A three-tier risk prevention system was developed based on the“source-pathway-receptor”framework:ozone-activated carbon pretreatment achieved 85%removal efficiency for pharmaceutical contaminants,ecological floating beds enhanced nitrogen and phosphorus retention by 40%-60%,and hydraulic regulation(flow velocity>0.1 m/s)effectively suppressed pathogen proliferation.The innovation of this study lies in establishing a chemical-biological-hydrological coupled risk quantification model for reclaimed water reuse scenarios.The hierarchical prevention standards have been incorporated into local reclaimed water management regulations,providing a scientific foundation and technical paradigm for sustainable landscape water replenishment. 展开更多
关键词 Recycled water systems Landscape hydration Ecological security assessment Risk management framework
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Research progress in digital auscultation:equipment and systems,characteristic parameters,and their application in diagnosis of pulmonary diseases and syndromes
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作者 Shuyi ZHANG Tao JIANG Jiatuo XU 《Digital Chinese Medicine》 2025年第1期20-27,共8页
Traditional Chinese medicine(TCM)auscultation has a long history,and with advancements in equipment and analytical methods,the quantitative analysis of auscultation parameters has determined.However,the complexity and... Traditional Chinese medicine(TCM)auscultation has a long history,and with advancements in equipment and analytical methods,the quantitative analysis of auscultation parameters has determined.However,the complexity and diversity of auscultation,along with variations in devices,analytical methods,and applications,bring challenges to its standardization and deeper application.This review presents the advancements in auscultation equipment and systems,auscultation characteristic parameters,and their application in the diagnosis of pulmonary diseases and syndromes over the past 10 years,while also exploring the progress and challenges of current digital research of auscultation.This review also proposes the establishment of standardized protocols for the collection and analysis of auscultation data,the incorporation of advanced artificial intelligence(AI)auscultation analysis methods,and an exploration of the diagnostic utility of auscultatory features in pulmonary diseases and syndromes,so as to provide more precise decision support for intelligent diagnosis of pulmonary diseases and syndromes. 展开更多
关键词 Digital auscultation Equipment and systems Characteristic parameters Pulmonary diseases and syndromes Intelligent diagnosis
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Heterogeneous radio frequency/underwater optical wireless communication relaying systems with MIMO scheme
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作者 Sai Li Liang Yang +1 位作者 Yusheng Sun Qianfen Jiao 《Digital Communications and Networks》 2025年第4期1017-1027,共11页
This paper studies a cooperative relay transmission system within the framework of Multiple-Input Multiple-Output Radio Frequency/Underwater Optical Wireless Communication(MIMO-RF/UOWC),aiming to establish sea-based h... This paper studies a cooperative relay transmission system within the framework of Multiple-Input Multiple-Output Radio Frequency/Underwater Optical Wireless Communication(MIMO-RF/UOWC),aiming to establish sea-based heterogeneous networks.In this setup,the RF links obey κ-μ fading,while the UOWC links undergo the generalized Gamma fading with the pointing error impairments.The relay operates under an Amplify-and-Forward(AF)protocol.Additionally,the attenuation caused by the Absorption and Scattering(AaS)is considered in UOWC links.The work yields precise results for the Average Channel Capacity(ACC),Outage Probability(OP),and average Bit Error Rate(BER).Furthermore,to reveal deeper insights,bounds on the ACC and asymptotic results for the OP and average BER are derived.The findings highlight the superior performance of MIMO-RF/UOWC AF systems compared to Single-Input-Single-Output(SISO)-RF/UOWC AF systems.Various factors affecting the Diversity Gain(DG)of the MIMO-RF/UOWC AF system include the number of antennas/apertures,fading parameters of both links,and pointing error parameters.Moreover,while an increase in the AaS effect can result in significant attenuation,it does not determine the achievable DG of the proposed MIMO-RF/UOWC AF relaying system. 展开更多
关键词 Sea-based heterogeneous networks Underwater wireless optical communication MIMO cooperative systems Absorption and scattering
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An Analysis of the Chemical Stress Field Under Potentiostatic Intermittent Titration Techniques for Interfacial Reaction-Controlled Systems
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作者 Kaikai Li Shichen Wang +1 位作者 Xiuling Shi Yan Huang 《Acta Mechanica Solida Sinica》 2025年第3期508-516,共9页
The potentiostatic intermittent titration technique(PITT)is widely used to determine the diffusion coefficient of ions in electrode materials for rechargeable batteries such as lithium-ion or sodium-ion batteries,pred... The potentiostatic intermittent titration technique(PITT)is widely used to determine the diffusion coefficient of ions in electrode materials for rechargeable batteries such as lithium-ion or sodium-ion batteries,predicated on the assumption that the insertion/extraction of ions in the host materials is governed by diffusion.However,in practical scenarios,the electrochemical process might be dominated by interfacial reaction kinetics rather than diffusion.The present work derives analytical equations for electric current by considering the finite interfacial reaction kinetics and small overpotentials during PITT measurements and further studies the chemical stress field induced by the interfacial reaction-controlled ion insertion.The exchange current density(j_(0))can be ascertained using the analytical equation,which dictates the magnitude and decay rate of the electric current during a PITT process.The electric current decays more rapidly,and consequently,the lithium concentration reaches equilibrium faster for larger values of j_(0).The magnitude of the chemical stress is independent of j_(0) but depends on the overpotential. 展开更多
关键词 Chemical stress Potentiostatic intermittent titration techniques Interfacial reaction-controlled systems Exchange current density Lithium diffusion
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Virtual sample diffusion generation method guided by large language model-generated knowledge for enhancing information completeness and zero-shot fault diagnosis in building thermal systems
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作者 Zhe SUN Qiwei YAO +7 位作者 Ling SHI Huaqiang JIN Yingjie XU Peng YANG Han XIAO Dongyu CHEN Panpan ZHAO Xi SHEN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第10期895-916,共22页
In the era of big data,data-driven technologies are increasingly leveraged by industry to facilitate autonomous learning and intelligent decision-making.However,the challenge of“small samples in big data”emerges whe... In the era of big data,data-driven technologies are increasingly leveraged by industry to facilitate autonomous learning and intelligent decision-making.However,the challenge of“small samples in big data”emerges when datasets lack the comprehensive information necessary for addressing complex scenarios,which hampers adaptability.Thus,enhancing data completeness is essential.Knowledge-guided virtual sample generation transforms domain knowledge into extensive virtual datasets,thereby reducing dependence on limited real samples and enabling zero-sample fault diagnosis.This study used building air conditioning systems as a case study.We innovatively used the large language model(LLM)to acquire domain knowledge for sample generation,significantly lowering knowledge acquisition costs and establishing a generalized framework for knowledge acquisition in engineering applications.This acquired knowledge guided the design of diffusion boundaries in mega-trend diffusion(MTD),while the Monte Carlo method was used to sample within the diffusion function to create information-rich virtual samples.Additionally,a noise-adding technique was introduced to enhance the information entropy of these samples,thereby improving the robustness of neural networks trained with them.Experimental results showed that training the diagnostic model exclusively with virtual samples achieved an accuracy of 72.80%,significantly surpassing traditional small-sample supervised learning in terms of generalization.This underscores the quality and completeness of the generated virtual samples. 展开更多
关键词 Information completeness Large language models(LLMs) Virtual sample generation Knowledge-guided Building air conditioning systems
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Protecting the Mental Health of Esports Players:A Qualitative Case Study on Their Stress,Coping Strategies,and Social Support Systems
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作者 Young-Vin Kim Hyunkyun Ahn 《International Journal of Mental Health Promotion》 2025年第9期1301-1334,共34页
Objectives:Recently,the global esports industry has experienced remarkable growth,leading to an expansion in the scale and influence of professional player communities.However,despite this outward growth,systems to pr... Objectives:Recently,the global esports industry has experienced remarkable growth,leading to an expansion in the scale and influence of professional player communities.However,despite this outward growth,systems to protect players’mental health remain inadequate.Comprehensive analysis of structural risk factors,including performance pressure,public evaluation,and career instability,remains insufficient.This study,aimed to explore stressors encountered by esports athletes,coping strategies,and the role of social support systems in safeguarding mental health.Using the transactional model of stress and coping,the job demands–resources model,and social support theory,the study adopts an integrated perspective to examine challenges faced by athletes in the competitive esports environment.Methods:A qualitative case study was conducted involving in-depth interviews and nonparticipant observations with 11 esports athletes who competed at national or international levels,as well as two team managers.Thematic analysis identified recurring patterns in the data,and credibility was ensured through triangulation and cross-review among researchers.Results:Esports athletes experience multiple interacting stressors,including performance demands,emotional strain duringmatches,and continuous evaluation on socialmedia.In response,they employed coping strategies—problem-focused,emotion-focused,and avoidance-based,which provided temporary relief but often led to burnout and self-regulation failure owing to absence of support systems.Social support networks had ambivalent effects:while offering comfort,they also intensified pressure through negative feedback and high expectations from fans and online communities.Conclusion:The findings show that mental health issues among esports athletes are not only related to individual factors but are closely linked to performance-driven structures,competitive environments,and social relationships.This study integrates the transactional model of stress and coping,the JobDemands–Resourcesmodel,and social support theoryto provide comprehensive analysis.It also offers practical recommendations,including psychological counseling,emotional labor programs,and improved communication with families and fan communities. 展开更多
关键词 Esports esports athletes players’mental health multifaceted stressors coping strategies social support systems job demands-resources model performance-driven demands
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Health Assessment and Driving Force Analysis of Cropland Systems in Typical Black Soil Region of Northeast China from 2003 to 2023
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作者 TIAN Xinyu JIANG Hailing +3 位作者 LUO Niu ZHANG Shuhan YU Hailin ZHANG Jingyi 《Chinese Geographical Science》 2025年第3期564-580,共17页
The health of cropland systems is directly related to the degree of food security guarantee,and the‘quantity-quality-ecology as a whole’protection is of great significance for maintaining the health of cropland syst... The health of cropland systems is directly related to the degree of food security guarantee,and the‘quantity-quality-ecology as a whole’protection is of great significance for maintaining the health of cropland systems.Taking the typical black soil region in Northeast China(TBSN)as an example,this paper combined the concept of‘quantity-quality-ecology as a whole’protection with crop-land systems health,constructed a health assessment model for cropland systems,and used Google Earth Engine to conduct a quantitat-ive analysis of the temporal and spatial evolution of cropland systems health in TBSN during 2003–2023.By coupling the geographical detector and the Multi-scale Geographically Weighted Regression(MGWR)model,the driving factors of cropland health changes were explored.The study finds that during the research period,the health status of cropland systems in TBSN showed a slight downward trend,and the distribution pattern of cropland systems health gradually shifted from‘better in the east’to‘high in the northeast and low in the southwest’.Changes in average annual sunshine duration,relative humidity,and precipitation had a significant impact on the spa-tial differentiation of cropland systems health in the early stages,and were considered as dominant factors.Meanwhile,the influence of dual dominant factors in the natural environment on cropland systems health is increasing.Furthermore,the MGWR model performed better in revealing the complex relationships between natural and social factors and changes in cropland systems health,demonstrating the significant spatial heterogeneity of the impacts of natural environment and human activities on cropland systems health.The re-search can provide scientific guidance for the sustainable development of TBSN and formulate more precise and effective cropland pro-tection policies. 展开更多
关键词 cropland systems health Google Earth Engine(GEE) Multi-scale Geographically Weighted Regression(MGWR)model Geographical Detector typical black soil region Northeast China
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Joint Probabilistic Scheduling and Resource Allocation for Wireless Networked Control Systems
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作者 Meng Zheng Lei Zhang Wei Liang 《IEEE/CAA Journal of Automatica Sinica》 2025年第1期258-260,共3页
Dear Editor,This letter presents a joint probabilistic scheduling and resource allocation method(PSRA) for 5G-based wireless networked control systems(WNCSs). As a control-aware optimization method, PSRA minimizes the... Dear Editor,This letter presents a joint probabilistic scheduling and resource allocation method(PSRA) for 5G-based wireless networked control systems(WNCSs). As a control-aware optimization method, PSRA minimizes the linear quadratic Gaussian(LQG) control cost of WNCSs by optimizing the activation probability of subsystems, the number of uplink repetitions, and the durations of uplink and downlink phases. Simulation results show that PSRA achieves smaller LQG control costs than existing works. 展开更多
关键词 subsystem activation probability linear quadratic gaussian control cost number uplink repetitions wireless networked control systems joint probabilistic scheduling resource allocation method psra linear quadratic gaussian lqg G based activation probability subsystems
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ESS-HPC与既有混凝土界面抗剪性能试验研究 被引量:1
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作者 吕昭旭 张冠军 +2 位作者 杨才千 杜文平 李郴 《混凝土》 北大核心 2025年第5期1-6,11,共7页
为研究早强自密实补偿收缩高性能混凝土(ESS-HPC)和普通混凝土(OCS)的界面黏结性能,设计并制作了27组试件,通过直剪试验分析ESS-HPC抗压强度、OCS表面处理方式、ESS-HPC养护龄期和界面剂等参数对界面黏结强度的影响。试验结果表明:ESS-H... 为研究早强自密实补偿收缩高性能混凝土(ESS-HPC)和普通混凝土(OCS)的界面黏结性能,设计并制作了27组试件,通过直剪试验分析ESS-HPC抗压强度、OCS表面处理方式、ESS-HPC养护龄期和界面剂等参数对界面黏结强度的影响。试验结果表明:ESS-HPC&OCS试件界面破坏形态主要分为界面破坏、界面剪切破坏以及界面和OCS基体部分破坏;当ESS-HPC强度等级从C60增加到C75时,试件的剪切黏结强度增加了近15%;对比未处理表面,凿毛+钻孔组试件的黏结强度可提升80.91%;在界面处使用丁苯乳液作为界面剂时,试件的黏结强度要高于其他界面剂的试件,但均低于无界面剂的现浇试件组,增加界面剂最高可降低界面黏结强度约26.1%;此外,界面黏结强度随着养护龄期的增加而呈增长趋势,且在28 d后这一趋势逐渐趋于稳定。因此,建议采用强度更高的ESS-HPC并在OCS表面进行钻孔和凿毛,以有效确保ESS-HPC的加固效果。 展开更多
关键词 早强自密实补偿收缩高性能混凝土(ess-HPC) 黏结性能 粗糙度 直剪试验
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Robust adaptive leaderless consensus of unknown non-minimum phase linear multi-agent systems subject to disturbances and/or unmodeled dynamics 被引量:1
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作者 Wenji Cao Gang Feng 《Journal of Automation and Intelligence》 2024年第2期92-100,共9页
This article investigates the problem of robust adaptive leaderless consensus for heterogeneous uncertain nonminimumphase linear multi-agent systems over directed communication graphs. Each agent is assumed tobe of un... This article investigates the problem of robust adaptive leaderless consensus for heterogeneous uncertain nonminimumphase linear multi-agent systems over directed communication graphs. Each agent is assumed tobe of unknown nominal dynamics and also subject to external disturbances and/or unmodeled dynamics. Anovel distributed robust adaptive control strategy is proposed. It is shown that the robust adaptive leaderlessconsensus problem is solved with the proposed control strategy under some sufficient conditions. Two examplesare provided to demonstrate the efficacy of the proposed control strategy. 展开更多
关键词 Cooperative control Non-minimum phase Leaderless consensus Multi-agent systems Robust adaptive control
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腹板植筋和填充ESS-HPC组合加固空心板梁抗剪性能研究
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作者 杜文平 杨才千 张冠军 《西安建筑科技大学学报(自然科学版)》 北大核心 2025年第4期511-519,共9页
针对空心板梁桥出现腹板斜裂缝病害,提出“腹板植筋+填充ESS-HPC”组合加固法.共设计9根空心板梁(Hollow core beam,简称HCB)试件,包括5根加固梁和4根对比梁,主要研究剪跨比和开口尺寸对HCB抗剪性能影响,同时提出抗剪承载力分析模型.试... 针对空心板梁桥出现腹板斜裂缝病害,提出“腹板植筋+填充ESS-HPC”组合加固法.共设计9根空心板梁(Hollow core beam,简称HCB)试件,包括5根加固梁和4根对比梁,主要研究剪跨比和开口尺寸对HCB抗剪性能影响,同时提出抗剪承载力分析模型.试验结果表明:与未加固梁相比,当剪跨比大于1且小于3时,加固梁的抗剪力学性能提升约60%.随着剪跨比增加,抗剪力学性能逐渐降低.“腹板植筋+填充ESS-HPC”组合加固法可提高剪压区的开裂荷载约50%,并降低箍筋应力.全开口可以降低初始刚度和裂缝宽度,但对极限荷载影响比较小.对比梁发生腹剪破坏模式且为脆性破坏,而加固梁发生弯剪破坏模式且为延性破坏.随着剪跨比增加,试验梁的受剪破坏模式由剪切破坏逐渐向弯剪破坏转变.最后,结合试验结果提出符合“腹板植筋+填充ESS-HPC”组合加固法的评估模型. 展开更多
关键词 ess-HPC 填充 腹板植筋 抗剪承承载力 评估模型
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Interpolated Bumpless Transfer Control for Asynchronously Switched Linear Systems
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作者 Shengao Lu Tong Wu +2 位作者 Lixian Zhang Jianan Yang Ye Liang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第7期1579-1590,共12页
This paper revisits the problem of bumpless transfer control(BTC) for discrete-time nondeterministic switched linear systems. The general case of asynchronous switching is considered for the first time in the field of... This paper revisits the problem of bumpless transfer control(BTC) for discrete-time nondeterministic switched linear systems. The general case of asynchronous switching is considered for the first time in the field of BTC for switched systems. A new approach called interpolated bumpless transfer control(IBTC) is proposed, where the bumpless transfer controllers are formulated with the combination of the two adjacent modedependent controller gains, and are interpolated for finite steps once the switching is detected. In contrast with the existing approaches, IBTC does not necessarily run through the full interval of subsystems, as well as possesses the time-varying controller gains(with more flexibility and less conservatism) achieved from a control synthesis allowing for the stability and other performance of the whole switched system. Sufficient conditions ensuring stability and H_(∞) performance of the underlying system by IBTC are developed, and numerical examples verify the theoretical findings. 展开更多
关键词 Asynchronous switching bumpless transfer H_∞control switched systems
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Opportunities to Improve the Quality of Environmental Reports and the Effectiveness of Environmental Impact Assessment: A Case of Electric Power Transmission Systems in Brazil
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作者 Vinícius Arthico Demori Marcelo Montaño 《Journal of Environmental Protection》 2024年第2期124-140,共17页
A good quality Environmental Impact Statement (EIS) is key for the effectiveness of Environmental Impact Assessment (EIA) processes and consequently to the acceptability of projects subject to EIA. The international l... A good quality Environmental Impact Statement (EIS) is key for the effectiveness of Environmental Impact Assessment (EIA) processes and consequently to the acceptability of projects subject to EIA. The international literature has contributed to the understanding of the essential aspects to be verified regarding the quality of EIS, offering a wide spectrum of good practice examples related to the content of the studies. Even so, there is a need for empirical studies that allow the identification of specific aspects related to the context of application of the EIS, which could lead to the identification of opportunities to improve both the quality of the reports and also the effectiveness of EIA. Therefore, the present paper is focused on the quality review of a number of EIS submitted to the Brazilian Federal Environmental Agency (Ibama) to instruct the assessment of electric power transmission systems. Based on the application of the EIS quality review package as proposed by Lee and Colley (1992), the outcomes reveal opportunities for improving the scope of EIA, analysis of alternatives, prediction of magnitude and the assessment of impact significance. Finally, the development and/or adaptation of a similar tool for the systematic review of the quality of EIA reports is recommended. 展开更多
关键词 Environmental Impact Assessment EFFECTIVENess Electric Energy Transmission systems
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Reviewing Stability Criteria for Positive Homogeneous Systems and Adding One for Discrete-Time Cases with Degree Less Than One
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作者 Nguyen Quang Tuan 《Circuits and Systems》 2024年第1期1-11,共11页
The article synthesizes and presents the results regarding the stability of positive homogeneous systems that have been researched and published in recent years. Next, we provide a sufficient condition for global expo... The article synthesizes and presents the results regarding the stability of positive homogeneous systems that have been researched and published in recent years. Next, we provide a sufficient condition for global exponential stability in the case of discrete-time positive homogeneous systems with an order less than one with time-varying delays. 展开更多
关键词 Exponential Stability Homogeneous systems Positive systems Positive Homogeneous systems
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A Systems Approach to Assessing Sustainability Capacity in Kalobeyei Refugee Settlement in Turkana County, Kenya
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作者 Anicet Adjahossou 《Open Journal of Applied Sciences》 2024年第4期833-848,共16页
Refugee settlements face several challenges in transitioning from a temporary planning approach to more sustainable settlements. This is mainly due to an increase in the number of forcibly displaced people over the la... Refugee settlements face several challenges in transitioning from a temporary planning approach to more sustainable settlements. This is mainly due to an increase in the number of forcibly displaced people over the last few decades, and the difficulties of sustainably providing social services that meet the required standards. The development of refugee settlements assumed that forcibly displaced people would return to their places or countries of origin. Unfortunately, displacement situations are prolonged indefinitely, forcing these people to spend most of their lives in conditions that are often deplorable and substandard, and therefore unsustainable. In most cases, the establishment of refugee settlements is triggered by an emergency caused by an influx of forcibly displaced people, who need to be accommodated urgently and provided with some form of international assistance and protection. This leaves little or no time for proper planning for long-term development as required. In addition, the current approach to temporary settlement harms the environment and can strain limited resources with ad hoc development models that have exacerbated difficulties. As a result, living conditions in refugee settlements have deteriorated over the last few decades and continue to pose challenges as to how best to design, plan, and sustain settlements over time. To contribute to addressing these challenges, this study proposes a new methodology supported by Model-Based Systems Engineering (MBSE) and a Systems Modeling Language (SysML) to develop a typical sustainable human settlement system model, which has functionally and operationally executed using a Systems Engineering (SE) approach. To assess the sustainability capacity of the proposed system, this work applies a matrix of crossed impact multiplication through a case study by conducting a system capacity interdependence analysis (SCIA) using the MICMAC methodology (Cross-impact matrix multiplication applied to classification) to assess the interdependency that exist between the sub-systems categories to deliver services at the system level. The sustainability analysis results based on capacity variables influence and dependency models shows that development activities in the settlement are unstable and, therefore, unsustainable since there is no apparent difference between the influential and dependent data used for the assessment. These results illustrate that an integrated system could improve human settlements’ sustainability and that capacity building in service delivery is beneficial and necessary. 展开更多
关键词 Humanitarian Settlement systems Engineering (SE) SUSTAINABILITY Capacity Assessment Model-Based systems Engineering (MBSE) systems Modeling Language (SysML)
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