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Research progress in methods of acquisition,structure elucidation,and quality control of Chinese herbal polysaccharides 被引量:1
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作者 Tingting Wang Baojie Zhu +1 位作者 Jing Zhao Shaoping Li 《Chinese Journal of Natural Medicines》 2025年第2期143-157,共15页
The therapeutic efficacy of traditional Chinese medicine has been widely acknowledged due to its extensive history of clinical effectiveness.However,the precise active components underlying each prescription remain in... The therapeutic efficacy of traditional Chinese medicine has been widely acknowledged due to its extensive history of clinical effectiveness.However,the precise active components underlying each prescription remain incompletely understood.Polysaccharides,as a major constituent of water decoctions—the most common preparation method for Chinese medicinals—may provide a crucial avenue for deepening our understanding of the efficacy principles of Chinese medicine and establishing a framework for its modern development.The structural complexity and diversity of Chinese herbal polysaccharides present significant challenges in their separation and analysis compared to small molecules.This paper aims to explore the potential of Chinese herbal polysaccharides efficiently by briefly summarizing recent advancements in polysaccharide chemical research,focusing on methods of acquisition,structure elucidation,and quality control. 展开更多
关键词 Chinese medicine POLYSAccHARIDE Extraction and purification Structural analysis Quality control
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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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Reporting quality of randomized controlled trials on acupuncture and manipulation for greater occipital neuralgia evaluated using the CONSORT statement and STRICTA checklist
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作者 Liu Liguo Qiu Mingwang +3 位作者 Huang Yanling Fan Zhiyong Wu Shan Guo Rusong 《中国组织工程研究》 北大核心 2025年第30期6566-6573,共8页
OBJECTIVE:In recent years,the number of clinical research reports on acupuncture and manipulation for the treatment of greater occipital neuralgia has gradually increased,but the quality is uneven.There is currently n... OBJECTIVE:In recent years,the number of clinical research reports on acupuncture and manipulation for the treatment of greater occipital neuralgia has gradually increased,but the quality is uneven.There is currently no literature evaluating the quality of published reports,which is not conducive to the promotion of clinical use of these therapies.Therefore,this article assessed the reporting quality of randomized controlled trials on acupuncture and manipulation for greater occipital neuralgia.METHODS:Cochrane Library,PubMed,Web of Science,Embase,China National Knowledge Infrastructure(CNKI),VIP,WanFang Data,and Chinese BioMedical Literature Database(CBM)from inception to May 20,2024 were searched.The reporting quality of included randomized controlled trials was independently evaluated by two investigators using the CONSORT statement,STRICTA checklist,and Cochrane bias of risk assessment tool.A third investigator resolved any disagreement.RESULTS:A total of 62 articles were included.Based on the CONSORT statement,59.46%(22/37)of all entries had a reporting rate of less than 50%,mainly including“Identification as a randomized trial in the title(1/62,1.61%),”“How sample size was determined(7/62,11.29%),”“Implementation(1/62,1.61%),”“Blinding(1/62,1.61%),”and“Reports of Funding(4/62,6.45%).”According to the STRICTA checklist,29.41%(5/17)of all entries had a reporting rate of less than 50%,mainly including“Details of other interventions(7/58,12.07%),”“Setting and context of treatment(0/58,0%),”and“Description of participating acupuncturists(0/58,0%).”CONCLUSION:The reporting quality of randomized controlled trials on acupuncture and manipulation therapy for greater occipital neuralgia remains low.Future researchers need to make greater efforts to strictly adhere to the CONSORT statement and STRICTA checklist during trial design,implementation,and reporting.This will facilitate the standardization of research in this field and enhance the reliability and reproducibility of the research results. 展开更多
关键词 reporting quality ACUPUNCTURE MANIPULATION CONSORT statement STRICTA checklist ROB clinical randomized controlled trials greater occipital neuralgia
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Application of Fructo-oligosaccharides Quality Control Chart in Milk Powder
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作者 Guoxia DUAN Lijun LIU +5 位作者 Ruilong XIE Xue HU Lunwei WU Jing CHEN Huili GONG Chunxia LIU 《Asian Agricultural Research》 2025年第1期35-37,共3页
The quality control chart of fructo-oligosaccharides in milk powder was established to determine whether the detection process and results are in control state.The content of fructo-oligosaccharides in milk powder con... The quality control chart of fructo-oligosaccharides in milk powder was established to determine whether the detection process and results are in control state.The content of fructo-oligosaccharides in milk powder control samples was determined by ion chromatography,and the quality control chart of fructo-oligosaccharides was established to analyze the controlled state.The results indicate that the median of the quality control chart is 1613.14 mg/100 g,and the standard deviation is 85.57 mg/100 g.The new quality control points were evaluated and analyzed,and the precision changed,but the mean value did not change.Further F test was conducted to determine that the precision did not change significantly,indicating that the test was in a statistical control state,and the detection process,method and results were controlled. 展开更多
关键词 Quality control chart FRUCTO-OLIGOSAccHARIDES Milk powder
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Efficient and fine-grained access control with fully-hidden policies for cloud-enabled IoT
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作者 Qi Li Gaozhan Liu +4 位作者 Qianqian Zhang Lidong Han Wei Chen Rui Li Jinbo Xiong 《Digital Communications and Networks》 2025年第2期473-481,共9页
Ciphertext-Policy Attribute-Based Encryption(CP-ABE)enables fine-grained access control on ciphertexts,making it a promising approach for managing data stored in the cloud-enabled Internet of Things.But existing schem... Ciphertext-Policy Attribute-Based Encryption(CP-ABE)enables fine-grained access control on ciphertexts,making it a promising approach for managing data stored in the cloud-enabled Internet of Things.But existing schemes often suffer from privacy breaches due to explicit attachment of access policies or partial hiding of critical attribute content.Additionally,resource-constrained IoT devices,especially those adopting wireless communication,frequently encounter affordability issues regarding decryption costs.In this paper,we propose an efficient and fine-grained access control scheme with fully hidden policies(named FHAC).FHAC conceals all attributes in the policy and utilizes bloom filters to efficiently locate them.A test phase before decryption is applied to assist authorized users in finding matches between their attributes and the access policy.Dictionary attacks are thwarted by providing unauthorized users with invalid values.The heavy computational overhead of both the test phase and most of the decryption phase is outsourced to two cloud servers.Additionally,users can verify the correctness of multiple outsourced decryption results simultaneously.Security analysis and performance comparisons demonstrate FHAC's effectiveness in protecting policy privacy and achieving efficient decryption. 展开更多
关键词 Access control Policy hiding Verifiable outsourced computation CLOUD IOT
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CC-OLIA:A dynamic congestion control algorithm for multipath QUIC in mobile networks
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作者 Haoyu Wang Yang Liu +5 位作者 Zijun Li Yu Zhang Wenjing Gong Tao Jiang Ting Bi Jiaxi Zhou 《Digital Communications and Networks》 2025年第4期1180-1190,共11页
High-quality services in today’s mobile networks require stable delivery of bandwidth-intensive network content.Multipath QUIC(MPQUIC),as a multipath protocol that extends QUIC,can utilize multiple paths to support s... High-quality services in today’s mobile networks require stable delivery of bandwidth-intensive network content.Multipath QUIC(MPQUIC),as a multipath protocol that extends QUIC,can utilize multiple paths to support stable and efficient transmission.The standard coupled congestion control algorithm in MPQUIC synchronizes these paths to manage congestion,meeting fairness requirements and improving transmission efficiency.However,current algorithms’Congestion Window(CWND)reduction approach significantly decreases CWND upon packet loss,which lowers effective throughput,regardless of the congestion origin.Furthermore,the uncoupled Slow-Start(SS)in MPQUIC leads to independent exponential CWND growth on each path,potentially causing buffer overflow.To address these issues,we propose the CC-OLIA,which incorporates Packet Loss Classifcation(PLC)and Coupled Slow-Start(CSS).The PLC distinguishes between congestion-induced and random packet losses,adjusting CWND reduction accordingly to maintain throughput.Concurrently,the CSS module coordinates CWND growth during the SS,preventing abrupt increases.Implementation on MININET shows that CC-OLIA not only maintains fair performance but also enhances transmission efficiency across diverse network conditions. 展开更多
关键词 MPQUIC Mobile network Congestion control Packet loss Slow start
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Institution Attribute Mining Technology for Access Control Based on Hybrid Capsule Network
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作者 Aodi Liu Xuehui Du +1 位作者 Na Wang Xiangyu Wu 《Computers, Materials & Continua》 2025年第4期1495-1513,共19页
Security attributes are the premise and foundation for implementing Attribute-Based Access Control(ABAC)mechanisms.However,when dealing with massive volumes of unstructured text big data resources,the current attribut... Security attributes are the premise and foundation for implementing Attribute-Based Access Control(ABAC)mechanisms.However,when dealing with massive volumes of unstructured text big data resources,the current attribute management methods based on manual extraction face several issues,such as high costs for attribute extraction,long processing times,unstable accuracy,and poor scalability.To address these problems,this paper proposes an attribute mining technology for access control institutions based on hybrid capsule networks.This technology leverages transfer learning ideas,utilizing Bidirectional Encoder Representations from Transformers(BERT)pre-trained language models to achieve vectorization of unstructured text data resources.Furthermore,we have designed a novel end-to-end parallel hybrid network structure,where the parallel networks handle global and local information features of the text that they excel at,respectively.By employing techniques such as attention mechanisms,capsule networks,and dynamic routing,effective mining of security attributes for access control resources has been achieved.Finally,we evaluated the performance level of the proposed attribute mining method for access control institutions through experiments on the medical referral text resource dataset.The experimental results show that,compared with baseline algorithms,our method adopts a parallel network structure that can better balance global and local feature information,resulting in improved overall performance.Specifically,it achieves a comprehensive performance enhancement of 2.06%to 8.18%in the F1 score metric.Therefore,this technology can effectively provide attribute support for access control of unstructured text big data resources. 展开更多
关键词 Access control ABAC model attribute mining capsule network deep learning
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An Improved Chicken Swarm Optimization Techniques Based on Cultural Algorithm Operators for Biometric Access Control
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作者 Jonathan Ponmile Oguntoye Sunday Adeola Ajagbe +4 位作者 Oluyinka Titilayo Adedeji Olufemi Olayanju Awodoye Abigail Bola Adetunji Elijah Olusayo Omidiora Matthew Olusegun Adigun 《Computers, Materials & Continua》 2025年第9期5713-5732,共20页
This study proposes a system for biometric access control utilising the improved Cultural Chicken Swarm Optimization(CCSO)technique.This approach mitigates the limitations of conventional Chicken Swarm Optimization(CS... This study proposes a system for biometric access control utilising the improved Cultural Chicken Swarm Optimization(CCSO)technique.This approach mitigates the limitations of conventional Chicken Swarm Optimization(CSO),especially in dealing with larger dimensions due to diversity loss during solution space exploration.Our experimentation involved 600 sample images encompassing facial,iris,and fingerprint data,collected from 200 students at Ladoke Akintola University of Technology(LAUTECH),Ogbomoso.The results demonstrate the remarkable effectiveness of CCSO,yielding accuracy rates of 90.42%,91.67%,and 91.25%within 54.77,27.35,and 113.92 s for facial,fingerprint,and iris biometrics,respectively.These outcomes significantly outperform those achieved by the conventional CSO technique,which produced accuracy rates of 82.92%,86.25%,and 84.58%at 92.57,63.96,and 163.94 s for the same biometric modalities.The study’s findings reveal that CCSO,through its integration of Cultural Algorithm(CA)Operators into CSO,not only enhances algorithm performance,exhibiting computational efficiency and superior accuracy,but also carries broader implications beyond biometric systems.This innovation offers practical benefits in terms of security enhancement,operational efficiency,and adaptability across diverse user populations,shaping more effective and resource-efficient access control systems with real-world applicability. 展开更多
关键词 Access control biometric technology chicken swarm optimization cultural algorithm pattern recognition
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Effectiveness of subcutaneous tunneling technique in reducing PICC dislodgement and malposition:a pilot multicenter randomized controlled trial
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作者 Yuan Sheng Wei Gao Sheng-Yi Dongye 《Frontiers of Nursing》 2025年第1期145-153,共9页
Objective:To evaluate the impact of subcutaneous tunneling on peripherally inserted central catheters(PICCs)dislodgement and malposition.Dislodged or malpositioned PICCs can lead to improper treatment.The subcutaneous... Objective:To evaluate the impact of subcutaneous tunneling on peripherally inserted central catheters(PICCs)dislodgement and malposition.Dislodged or malpositioned PICCs can lead to improper treatment.The subcutaneous tunneling strategy may be effective,but there is insufficient evidence,and proximal movement has not been explored.Methods:We randomized 630 patients who needed PICCs placement to either the tunneled PICCs(experimental group)or the non-tunneled PICCs(control group).Dislodgement and malposition of the catheter were the primary outcomes,and catheter-related infection(CRI)and catheter-related thrombosis(CRT)were the secondary outcomes.Results:Subcutaneous tunneling does not significantly reduce distal catheter movement,but it significantly reduces proximal catheter movement(4.3%vs.9.9%,P=0.007),which may explain the lower incidence of CRI(2.0%vs.5.3%,P=0.030)and CRT(3.6%vs.12.5%,P<0.001).Conclusions:Although subcutaneous tunneling does not significantly improve catheter prolapse,it should still be used clinically because proximal catheter movement can be a more serious problem associated with CRI and CRT. 展开更多
关键词 CATHETERIZATION COMPLICATIONS peripheral adverse effects randomized controlled trial tunneled multicenter study
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Key Technologies for Security Control of 5G-R Terminal and Application Access
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作者 MA Jun LIU Chang +2 位作者 LIN Wei LI Hui HAN Xu(Translated) 《Chinese Railways》 2025年第1期3-10,共8页
Terminals and their access represent a vulnerable aspect in the security framework of 5G-railway(5G-R)system.To enhance the control of 5G-R terminals and their access to applications,this paper analyzes the applicatio... Terminals and their access represent a vulnerable aspect in the security framework of 5G-railway(5G-R)system.To enhance the control of 5G-R terminals and their access to applications,this paper analyzes the application scenarios,operational modes,services supported by 5G-R terminals,and the data paths between these terminals and the connected railway application service systems.Further analysis concentrates on the security risks posed by the characteristics of intelligent 5G-R handheld terminals,lightweight Internet of Things(IoT)communication terminals,and onboard integrated wireless transmission equipment with public-private convergence.In light of the risks above,this paper presents the terminal security control requirements.Furthermore,based on the planned architecture of the 5G-R system and security technologies such as terminal identity authentication and behavior auditing,the paper proposes a solution package for the 5G-R terminal security control system,including the overall architecture,functional implementation,and interface configuration.These solutions aim to achieve unified control over the admission and access of 5G-R handheld terminals,IoT communication terminals,and onboard integrated wireless communication equipment to railway application systems.Additionally,they enable the security control and analysis of terminal behaviors and application data,facilitate the security management of terminals,and ensure the secure release,download,and installation of mobile applications. 展开更多
关键词 5G-R 5G-R terminal application access security control communication interface
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Extinction and Optimal Control of Stochastic Epidemic Model with Multiple Vaccinations and Time Delay
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作者 YANG Rujie QIU Hong JU Xuewei 《数学理论与应用》 2025年第2期110-121,共12页
In this paper,based on the SVIQR model we develop a stochastic epidemic model with multiple vaccinations and time delay.Firstly,we prove the existence and uniqueness of the global positive solution of the model,and co... In this paper,based on the SVIQR model we develop a stochastic epidemic model with multiple vaccinations and time delay.Firstly,we prove the existence and uniqueness of the global positive solution of the model,and construct suitable functions to obtain sufficient conditions for disease extinction.Secondly,in order to effectively control the spread of the disease,appropriate control strategies are formulated by using optimal control theory.Finally,the results are verified by numerical simulation. 展开更多
关键词 Stochastic epidemic model Multiple vaccinations Extinction of disease Isolation delay Optimal control
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DRG-DCC:A Driving Risk Gaming Based Distributed Congestion Control Method for C-V2X Technology
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作者 Lingqiu Zeng Peibing Sa +4 位作者 Qingwen Han Lei Ye Letian Yang Cheng Zhang Jiqiang Cheng 《Computers, Materials & Continua》 2025年第5期2059-2086,共28页
Congestion control is an inherent challenge of V2X(Vehicle to Everything)technologies.Due to the use of a broadcasting mechanism,channel congestion becomes severe with the increase in vehicle density.The researchers s... Congestion control is an inherent challenge of V2X(Vehicle to Everything)technologies.Due to the use of a broadcasting mechanism,channel congestion becomes severe with the increase in vehicle density.The researchers suggested reducing the frequency of packet dissemination to relieve congestion,which caused a rise in road driving risk.Obviously,high-risk vehicles should be able to send messages timely to alarm surrounding vehicles.Therefore,packet dissemination frequency should be set according to the corresponding vehicle’s risk level,which is hard to evaluate.In this paper,a two-stage fuzzy inference model is constructed to evaluate a vehicle’s risk level,while a congestion control algorithm DRG-DCC(Driving Risk Game-Distributed Congestion Control)is proposed.Moreover,HPSO is employed to find optimal solutions.The simulation results show that the proposed method adjusts the transmission frequency based on driving risk,effectively striking a balance between transmission delay and channel busy rate. 展开更多
关键词 Distributed congestion control fuzzy inference driving risk evaluation game theory Nash equilibrium
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Effects of Internet-Based Acceptance and Commitment Therapy on College Students’Mental Health: A Randomized Controlled Trial
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作者 Jing Wang Shuanghu Fang +1 位作者 Zihua Li Shaoyong Ma 《International Journal of Mental Health Promotion》 2025年第6期845-861,共17页
Objectives:College students face increasing mental health challenges.Although Acceptance and CommitmentTherapy(ACT)is effective,the efficacy of Internet-based ACT(iACT)needs further exploration.Methods:This study exam... Objectives:College students face increasing mental health challenges.Although Acceptance and CommitmentTherapy(ACT)is effective,the efficacy of Internet-based ACT(iACT)needs further exploration.Methods:This study examines the efficacy of iACT on college students’mental health through a randomized controlled trial.We recruited 90 college students(19.16±1.02 years old)and randomly divided them into the iACT group,face-to-face ACT group,and control group.The effects of the interventions were evaluated using the comprehensive assessment of ACT processes(CompACT)and the Depression Anxiety Stress Scales(DASS-21).Results:Two-factor repeated measures ANOVA revealed a significant time main effect of iACT.Face-to-face ACT and iACT effectively improved college students’psychological flexibility[F(2,83)=18.78,p<0.001,η^(2)=0.18]and alleviated their negative emotions[F(2,82)=41.17,p<0.001,η^(2)=0.36].Face-to-face ACT exhibited sustained effects on improving participants’psychological flexibility and alleviating their negative emotions(p<0.001),while iACT showed no sustained effect on improving participants’psychological flexibility(p>0.05).Conclusion:While iACT and face-to-face ACT are effective shortterm interventions,face-to-face ACT demonstrates superior sustainability.Integrating guided sessions into iACT may enhance long-term outcomes.These findings advocate for blended interventions to address college students’mental health needs,particularly in resource-limited settings. 展开更多
关键词 Internet-based acceptance and commitment therapy mental health college students randomized controlled trial
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Global integration design method of acceleration and deceleration control schedule for variable cycle engine
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作者 Ying CHEN Sangwei LU +1 位作者 Wenxiang ZHOU Jinquan HUANG 《Chinese Journal of Aeronautics》 2025年第5期248-261,共14页
Variable Cycle Engine(VCE)serves as the core system in achieving future advanced fighters with cross-generational performance and mission versatility.However,the resultant complex configuration and strong coupling of ... Variable Cycle Engine(VCE)serves as the core system in achieving future advanced fighters with cross-generational performance and mission versatility.However,the resultant complex configuration and strong coupling of control parameters present significant challenges in designing acceleration and deceleration control schedules.To thoroughly explore the performance potential of engine,a global integration design method for acceleration and deceleration control schedule based on inner and outer loop optimization is proposed.The outer loop optimization module employs Integrated Surrogate-Assisted Co-Differential Evolutionary(ISACDE)algorithm to optimize the variable geometry adjustment laws based on B-spline curve,and the inner loop optimization module adopts the fixed-state method to design the open-loop fuel–air ratio control schedules,which are aimed at minimizing the acceleration and deceleration time under multiple constraints.Simulation results demonstrate that the proposed global integration design method not only furthest shortens the acceleration and deceleration time,but also effectively safeguards the engine from overlimit. 展开更多
关键词 control schedule design Acceleration and deceleration Variablecycle engine Fixed-states method Co-differential evolutionary algorithm
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Federated Learning and Blockchain Framework for Scalable and Secure IoT Access Control
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作者 Ammar Odeh Anas Abu Taleb 《Computers, Materials & Continua》 2025年第7期447-461,共15页
The increasing deployment of Internet of Things(IoT)devices has introduced significant security chal-lenges,including identity spoofing,unauthorized access,and data integrity breaches.Traditional security mechanisms r... The increasing deployment of Internet of Things(IoT)devices has introduced significant security chal-lenges,including identity spoofing,unauthorized access,and data integrity breaches.Traditional security mechanisms rely on centralized frameworks that suffer from single points of failure,scalability issues,and inefficiencies in real-time security enforcement.To address these limitations,this study proposes the Blockchain-Enhanced Trust and Access Control for IoT Security(BETAC-IoT)model,which integrates blockchain technology,smart contracts,federated learning,and Merkle tree-based integrity verification to enhance IoT security.The proposed model eliminates reliance on centralized authentication by employing decentralized identity management,ensuring tamper-proof data storage,and automating access control through smart contracts.Experimental evaluation using a synthetic IoT dataset shows that the BETAC-IoT model improves access control enforcement accuracy by 92%,reduces device authentication time by 52%(from 2.5 to 1.2 s),and enhances threat detection efficiency by 7%(from 85%to 92%)using federated learning.Additionally,the hybrid blockchain architecture achieves a 300%increase in transaction throughput when comparing private blockchain performance(1200 TPS)to public chains(300 TPS).Access control enforcement accuracy was quantified through confusion matrix analysis,with high precision and minimal false positives observed across access decision categories.Although the model presents advantages in security and scalability,challenges such as computational overhead,blockchain storage constraints,and interoperability with existing IoT systems remain areas for future research.This study contributes to advancing decentralized security frameworks for IoT,providing a resilient and scalable solution for securing connected environments. 展开更多
关键词 Blockchain IoT security access control federated learning merkle tree decentralized identity manage-ment threat detection
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High-Temperature Stable Dispersed Particle Gel for Enhanced Profile Control in Carbon Capture,Utilization,and Storage(CCUS)Applications
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作者 Lin Du Yao-Yu Xiao +2 位作者 Zhi-Chao Jiang Hongbo Zeng Huazhou Li 《Engineering》 2025年第5期128-140,共13页
CO_(2)-responsive gels,which swell upon contact with CO_(2),are widely used for profile control to plug high-permeability gas flow channels in carbon capture,utilization,and storage(CCUS)applications in oil reser-voir... CO_(2)-responsive gels,which swell upon contact with CO_(2),are widely used for profile control to plug high-permeability gas flow channels in carbon capture,utilization,and storage(CCUS)applications in oil reser-voirs.However,the use of these gels in high-temperature CCUS applications is limited due to their rever-sible swelling behavior at elevated temperatures.In this study,a novel dispersed particle gel(DPG)suspension is developed for high-temperature profile control in CCUS applications.First,we synthesize a double-network hydrogel consisting of a crosslinked polyacrylamide(PAAm)network and a crosslinked sodium alginate(SA)network.The hydrogel is then sheared in water to form a pre-prepared DPG suspen-sion.To enhance its performance,the gel particles are modified by introducing potassium methylsilan-etriolate(PMS)upon CO_(2) exposure.Comparing the particle size distributions of the modified and pre-prepared DPG suspension reveals a significant swelling of gel particles,over twice their original size.Moreover,subjecting the new DPG suspension to a 100℃ environment for 24 h demonstrates that its gel particle sizes do not decrease,confirming irreversible swelling,which is a significant advantage over the traditional CO_(2)-responsive gels.Thermogravimetric analysis further indicates improved thermal sta-bility compared to the pre-prepared DPG particles.Core flooding experiments show that the new DPG suspension achieves a high plugging efficiency of 95.3%in plugging an ultra-high permeability sandpack,whereas the pre-prepared DPG suspension achieves only 82.8%.With its high swelling ratio,irreversible swelling at high temperatures,enhanced thermal stability,and superior plugging performance,the newly developed DPG suspension in this work presents a highly promising solution for profile control in high-temperature CCUS applications. 展开更多
关键词 Carbon capture utilization and storage Profile control Dispersed particle gel Double-network hydrogel Irreversible swelling
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碳捕集与封存(CCS)项目关键风险识别与分析 被引量:2
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作者 陈媛 陈田丰 徐英华 《天津大学学报(社会科学版)》 2025年第3期222-230,共9页
在国家“双碳”目标的驱动下,将二氧化碳捕集、封存来缓解气候变化变得尤为重要。然而,碳捕集与封存(CCS)项目在实施过程中仍存在各种风险,且不同风险间会相互影响。文章运用文献分析法归纳CCS项目风险清单,进而构建出风险网络模型。同... 在国家“双碳”目标的驱动下,将二氧化碳捕集、封存来缓解气候变化变得尤为重要。然而,碳捕集与封存(CCS)项目在实施过程中仍存在各种风险,且不同风险间会相互影响。文章运用文献分析法归纳CCS项目风险清单,进而构建出风险网络模型。同时,从社会网络视角探究CCS项目风险网络特征并识别关键风险节点,进而提出风险防范和规避的对策建议。研究发现,CCS项目风险网络具有一定的连通性,技术成本风险、二氧化碳泄露风险、选址风险、政策法规风险是网络中的关键节点,需要给予重点关注。以期为相关决策者开展CCS项目风险管理提供理论依据,促进该类项目的可持续发展。 展开更多
关键词 ccS 风险识别 风险分析 社会网络
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IgA肾病患者血清CCR2、CCL2水平与病情、疾病转归的关系 被引量:1
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作者 杨小华 何绍沿 +2 位作者 罗富秀 全强 景海宁 《转化医学杂志》 2025年第4期92-96,共5页
目的探讨IgA肾病患者血清CC趋化因子受体2(CCR2)及趋化因子CC基序配体2(CCL2)水平与病情严重程度及疾病转归的关系。方法选取2020年1月至2022年12月广元市中心医院收治的106例Ig A肾病患者作为研究组及100例体检的健康体检者作为对照组... 目的探讨IgA肾病患者血清CC趋化因子受体2(CCR2)及趋化因子CC基序配体2(CCL2)水平与病情严重程度及疾病转归的关系。方法选取2020年1月至2022年12月广元市中心医院收治的106例Ig A肾病患者作为研究组及100例体检的健康体检者作为对照组。根据肾间质纤维化程度将患者分为轻度组(42例)、中度组(35例)和重度组(29例)。随访2年后,根据疾病转归情况分为转归良好组78例(73.58%)与转归不良组28例(26.42%)。收集所有IgA肾病患者的临床资料及入院时血清CCR2、CCL2水平,分析其与IgA肾病患者病情的相关性,采用多因素Logistic回归分析影响患者转归不良的危险因素。结果研究组患者血清CCR2、CCL2水平高于对照组(P<0.05)。且随着IgA肾病患者病情加重而逐渐升高(P<0.05)。Spearman相关分析显示,IgA肾病患者血清CCR2(r=0.613)和CCL2(r=0.684)水平与病情严重程度呈正相关(P<0.05)。在为期2年的随访中,转归不良组24 h尿蛋白定量、血清CCR2、血清CCL2、血尿素氮、血清肌酐、尿酸均高于转归良好组,eGFR低于转归良好组(P<0.05)。多因素Logistic回归分析显示,血清肌酐(OR=2.277,95%CI:1.048~4.949),24 h尿蛋白定量(OR=2.502,95%CI:1.226~5.106),血清CCR2(OR=3.093,95%CI:1.711~5.590),血清CCL2(OR=3.800,95%CI:2.066~6.991)是影响Ig A肾病患者疾病转归的独立危险因素(P<0.05)。结论Ig A肾病患者血清CCR2、CCL2水平与病情严重程度及预后密切相关,可能作为评估疾病进展和预后的潜在生物学标志物。 展开更多
关键词 IGA肾病 cc趋化因子受体2 趋化因子cc基序配体2 疾病转归
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东亚峰会国家CCS现状与合作展望
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作者 张鑫刚 刘佳 +2 位作者 方圆 黄文韬 徐晶晶 《中国矿业》 北大核心 2025年第9期65-73,共9页
东亚峰会参与国作为全球能源消费核心区与碳捕集与封存(CCS)技术发展前沿区域,在推进碳中和进程中具有重要战略地位。本文系统梳理东亚峰会成员国CCS技术发展现状与区域合作进展,通过国别案例分析、政策框架比较与跨国项目评估,揭示区... 东亚峰会参与国作为全球能源消费核心区与碳捕集与封存(CCS)技术发展前沿区域,在推进碳中和进程中具有重要战略地位。本文系统梳理东亚峰会成员国CCS技术发展现状与区域合作进展,通过国别案例分析、政策框架比较与跨国项目评估,揭示区域合作潜力与关键挑战。东亚峰会国家呈现出差异化发展格局,发达国家CCS战略目标明确,财政投入持续稳定,通过系统性开展地质封存潜力评估指导项目部署,注重基础研究到商业转化,并且政策法规体系日趋完善。美国在CCS技术研发与商业化部署方面占据绝对主导地位;澳大利亚建立了系统化的研发模式,形成了从基础研究、技术转化到商业化应用的完整路径;日本构建了技术研发、政策供给、企业协同的三位一体体系;韩国立法构建CCS全产业链。东盟国家CCS发展水平呈现显著分化,其中,印度尼西亚、越南引领区域进程,政策法规框架初建且不平衡,项目阶段差异大。区域合作聚焦跨境运输网络构建、监测技术联合研发、封存潜力协同评估、政策框架协调等,形成了新加坡-印度尼西亚、韩国-马来西亚等跨国合作模式。为实现《巴黎协定》目标,东亚峰会国家间需要深化CCS技术研发合作,完善政策协同机制,强化基础设施互联。东亚峰会国家有望通过深化技术协同、政策衔接与设施联通,建成全球领先的CCS技术应用示范区,为碳中和目标提供区域性实践参考。 展开更多
关键词 东亚峰会 碳捕集与封存(ccS) 能源 碳中和 碳减排
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基于实物期权的燃煤电厂CCUS投资决策研究
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作者 聂鹏飞 高哲远 王喜平 《洁净煤技术》 北大核心 2025年第10期1-8,共8页
碳捕集利用与封存(CCUS)作为减缓气候变化的一项关键技术,得到了国际社会的广泛关注。但由于受到技术、成本、政策以及商业模式和公众接受度等诸多因素制约,CCUS商业化发展仍面临多重挑战。从燃煤电厂视角出发,考虑集“碳捕获–利用–... 碳捕集利用与封存(CCUS)作为减缓气候变化的一项关键技术,得到了国际社会的广泛关注。但由于受到技术、成本、政策以及商业模式和公众接受度等诸多因素制约,CCUS商业化发展仍面临多重挑战。从燃煤电厂视角出发,考虑集“碳捕获–利用–封存”于一体的商业模式下CCUS投资决策问题。基于实物期权理论,构建考虑碳价格不确定性及CCUS投资成本递减情况下CCUS投资决策模型,并通过数值仿真求解得到CO_(2)不同利用率下燃煤电厂CCUS投资的期权价值和投资时机。最后,分析碳价波动率和额外电力配额、电价补贴、投资补贴等不同激励政策对燃煤电厂CCUS投资决策的影响。结果表明:①CO_(2)利用率越高越能促进CCUS项目的投资,当CO_(2)利用率高于47.27%时,燃煤电厂可立即投资;②稳定的碳价有助于促进CCUS投资;③电价补贴是最有效的激励政策。 展开更多
关键词 ccS ccUS 投资决策 实物期权 一体化模式
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