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Optimizing nitrogen management can improve stem lodging resistance and stabilize the grain yield of japonica rice in rice-crayfish coculture systems
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作者 Qiang Xu Jingyong Li +5 位作者 Hui Gao Xinyi Yang Zhi Dou Xiaochun Yuan Weiyan Gao Hongcheng Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第12期3983-3997,共15页
Nitrogen(N)significantly affects rice yield and lodging resistance.Previous studies have primarily investigated the impact of N management on rice lodging in conventional rice monoculture(RM);however,few studies have ... Nitrogen(N)significantly affects rice yield and lodging resistance.Previous studies have primarily investigated the impact of N management on rice lodging in conventional rice monoculture(RM);however,few studies have performed such investigations in rice-crayfish coculture(RC).We hypothesized that RC would increase rice lodging risk and that optimizing N application practices would improve rice lodging resistance without affecting food security.We conducted a two-factor(rice farming mode and N management practice)field experiment from2021 to 2022 to test our hypothesis.The rice farming modes included RM and RC,and the N management practices included no nitrogen fertilizer,conventional N application,and optimized N treatment.The rice yield and lodging resistance characteristics,such as morphology,mechanical and chemical characteristics,anatomic structure,and gene expression levels,were analyzed and compared among the treatments.Under the same N application practice,RC decreased the rice yield by 11.1-24.4% and increased the lodging index by 19.6-45.6% compared with the values yielded in RM.In RC,optimized N application decreased the plant height,panicle neck node height,center of gravity height,bending stress,and lodging index by 4.0-4.8%,5.2-7.8%,0.5-4.5%,5.5-10.5%,and 1.8-19.5%,respectively,compared with those in the conventional N application practice.Furthermore,it increased the culm diameter,culm wall thickness,breaking strength,and non-structural and structural carbohydrate content by 0.8-4.9%,2.2-53.1%,13.5-19.2%,2.2-24.7%,and 31.3-87.2%,respectively.Optimized N application increased sclerenchymal and parenchymal tissue areas of the vascular bundle at the culm wall of the base second internode.Furthermore,optimized N application upregulated genes involved in lignin and cellulose synthesis,thereby promoting lower internodes on the rice stem and enhancing lodging resistance.Optimized N application in RC significantly reduced the lodging index by 1.8-19.5%and stabilized the rice yield(>8,570 kg ha~(-1)on average).This study systematically analyzed and compared the differences in lodging characteristics between RM and RC.The findings will aid in the development of more efficient practices for RC that will reduce N fertilizer application. 展开更多
关键词 RICE lodging resistance nitrogen regulation anatomical structure rice-crayfish coculture
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New food sources and production systems:a comparison of international regulations and China’s advancements in novel foods with synthetic biology
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作者 Xin Liu Di Wu +1 位作者 Yi Shao Yongning Wu 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2519-2542,共24页
The global shift towards sustainable food systems has sparked innovations in food sources and production systems,including cell-based meat,plant-based food products,precision fermentation,and 3D food printing.These ad... The global shift towards sustainable food systems has sparked innovations in food sources and production systems,including cell-based meat,plant-based food products,precision fermentation,and 3D food printing.These advancements pose regulatory challenges and opportunities,with China emerging as a critical player in adopting and regulating new food technologies.This review explores the international landscape of new food sources and production systems(NFPS),focusing on China’s role and regulatory approaches compared to global practices.Through this comparative analysis,we aim to contribute to the ongoing dialogue on food safety regulation,offering insights and recommendations for policymakers,industry stakeholders,and researchers engaged in the global food system’s evolution.This comprehensive overview underscores the dynamic nature of regulatory frameworks governing NFPS,highlighting the international efforts to ensure food safety,consumer protection,and the sustainable evolution of the food industry. 展开更多
关键词 New food sources Food production system Food safety International regulation Synthetic biology China
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Functions of nuclear factor Y in nervous system development,function and health
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作者 Pedro Moreira Roger Pocock 《Neural Regeneration Research》 SCIE CAS 2025年第10期2887-2894,共8页
Nuclear factor Y is a ubiquitous heterotrimeric transcription factor complex conserved across eukaryotes that binds to CCAAT boxes,one of the most common motifs found in gene promoters and enhancers.Over the last 30 y... Nuclear factor Y is a ubiquitous heterotrimeric transcription factor complex conserved across eukaryotes that binds to CCAAT boxes,one of the most common motifs found in gene promoters and enhancers.Over the last 30 years,research has revealed that the nuclear factor Y complex controls many aspects of brain development,including differentiation,axon guidance,homeostasis,disease,and most recently regeneration.However,a complete understanding of transcriptional regulatory networks,including how the nuclear factor Y complex binds to specific CCAAT boxes to perform its function remains elusive.In this review,we explore the nuclear factor Y complex’s role and mode of action during brain development,as well as how genomic technologies may expand understanding of this key regulator of gene expression. 展开更多
关键词 axon guidance CCAAT boxes neuronal degeneration neuronal differentiation neuronal regeneration nuclear factor Y complex transcription factor transcriptional regulation
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Adaptive Optimal Output Regulation of Interconnected Singularly Perturbed Systems With Application to Power Systems
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作者 Jianguo Zhao Chunyu Yang +2 位作者 Weinan Gao Linna Zhou Xiaomin Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期595-607,共13页
This article studies the adaptive optimal output regulation problem for a class of interconnected singularly perturbed systems(SPSs) with unknown dynamics based on reinforcement learning(RL).Taking into account the sl... This article studies the adaptive optimal output regulation problem for a class of interconnected singularly perturbed systems(SPSs) with unknown dynamics based on reinforcement learning(RL).Taking into account the slow and fast characteristics among system states,the interconnected SPS is decomposed into the slow time-scale dynamics and the fast timescale dynamics through singular perturbation theory.For the fast time-scale dynamics with interconnections,we devise a decentralized optimal control strategy by selecting appropriate weight matrices in the cost function.For the slow time-scale dynamics with unknown system parameters,an off-policy RL algorithm with convergence guarantee is given to learn the optimal control strategy in terms of measurement data.By combining the slow and fast controllers,we establish the composite decentralized adaptive optimal output regulator,and rigorously analyze the stability and optimality of the closed-loop system.The proposed decomposition design not only bypasses the numerical stiffness but also alleviates the high-dimensionality.The efficacy of the proposed methodology is validated by a load-frequency control application of a two-area power system. 展开更多
关键词 Adaptive optimal control decentralized control output regulation reinforcement learning(RL) singularly perturbed systems(SPSs)
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Sensing-Communication-Computing-Control Closed Loop for NOMA-UAV Systems
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作者 Lei Chengleyang Feng Wei +4 位作者 Wang Jue Wang Yanmin Jin Shi Yin Liuguo Ge Ning 《China Communications》 SCIE CSCD 2024年第8期89-103,共15页
In the areas without terrestrial communication infrastructures,unmanned aerial vehicles(UAVs)can be utilized to serve field robots for mission-critical tasks.For this purpose,UAVs can be equipped with sensing,communic... In the areas without terrestrial communication infrastructures,unmanned aerial vehicles(UAVs)can be utilized to serve field robots for mission-critical tasks.For this purpose,UAVs can be equipped with sensing,communication,and computing modules to support various requirements of robots.In the task process,different modules assist the robots to perform tasks in a closed-loop way,which is referred to as a sensing-communication-computing-control(SC3)loop.In this work,we investigate a UAV-aided system containing multiple SC^(3)loops,which leverages non-orthogonal multiple access(NOMA)for efficient resource sharing.We describe and compare three different modelling levels for the SC^(3)loop.Based on the entropy SC^(3)loop model,a sum linear quadratic regulator(LQR)control cost minimization problem is formulated by optimizing the communication power.Further for the assure-to-be-stable case,we show that the original problem can be approximated by a modified user fairness problem,and accordingly gain more insights into the optimal solutions.Simulation results demonstrate the performance gain of using NOMA in such task-oriented systems,as well as the superiority of our proposed closed-loop-oriented design. 展开更多
关键词 closed loop linear quadratic regulator(LQR) non-orthogonal multiple access(NOMA) power allocation unmanned aerial vehicle(UAV)
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Event-triggered robust cooperative output regulation for a class of linear multi-agent systems with an unknown exosystem
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作者 Yangyang Qian Lu Liu 《Journal of Automation and Intelligence》 2024年第2期119-127,共9页
This paper investigates the robust cooperative output regulation problem for a class of heterogeneousuncertain linear multi-agent systems with an unknown exosystem via event-triggered control (ETC). By utilizingthe in... This paper investigates the robust cooperative output regulation problem for a class of heterogeneousuncertain linear multi-agent systems with an unknown exosystem via event-triggered control (ETC). By utilizingthe internal model approach and the adaptive control technique, a distributed adaptive internal model isconstructed for each agent. Then, based on this internal model, a fully distributed ETC strategy composed ofa distributed event-triggered adaptive output feedback control law and a distributed dynamic event-triggeringmechanism is proposed, in which each agent updates its control input at its own triggering time instants. It isshown that under the proposed ETC strategy, the robust cooperative output regulation problem can be solvedwithout requiring either the global information associated with the communication topology or the bounds ofthe uncertain or unknown parameters in each agent and the exosystem. A numerical example is provided toillustrate the effectiveness of the proposed control strategy. 展开更多
关键词 Adaptive control Event-triggered control Internal model Multi-agent systems Output regulation
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Research on Regulation Method of Energy Storage System Based on Multi-Stage Robust Optimization
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作者 Zaihe Yang Shuling Wang +3 位作者 Runhang Zhu Jiao Cui Ji Su Liling Chen 《Energy Engineering》 EI 2024年第3期807-820,共14页
To address the scheduling problem involving energy storage systems and uncertain energy,we propose a method based on multi-stage robust optimization.This approach aims to regulate the energy storage system by using a ... To address the scheduling problem involving energy storage systems and uncertain energy,we propose a method based on multi-stage robust optimization.This approach aims to regulate the energy storage system by using a multi-stage robust optimal control method,which helps overcome the limitations of traditional methods in terms of time scale.The goal is to effectively utilize the energy storage power station system to address issues caused by unpredictable variations in environmental energy and fluctuating load throughout the day.To achieve this,a mathematical model is constructed to represent uncertain energy sources such as photovoltaic and wind power.The generalized Benders Decomposition method is then employed to solve the multi-stage objective optimization problem.By decomposing the problem into a series of sub-objectives,the system scale is effectively reduced,and the algorithm’s convergence ability is improved.Compared with other algorithms,the multi-stage robust optimization model has better economy and convergence ability and can be used to guide the power dispatching of uncertain energy and energy storage systems. 展开更多
关键词 Multi-stage robust optimization energy storage system regulation methods output uncertainty
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Research Progress on the Association Between Gut Microbiota and Respiratory System Diseases
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作者 Jing Liu Ruilin Sun 《Proceedings of Anticancer Research》 2024年第3期68-73,共6页
This paper aims to review the association between gut microbiota and respiratory system diseases, and explore their potential mechanisms and clinical significance. Gut microbiota, as an important microbial ecosystem i... This paper aims to review the association between gut microbiota and respiratory system diseases, and explore their potential mechanisms and clinical significance. Gut microbiota, as an important microbial ecosystem in the human body, has profound effects on host health. Recent studies have shown that the imbalance of gut microbiota is closely related to the occurrence and development of respiratory system diseases, including asthma, chronic obstructive pulmonary disease (COPD), and pneumonia. We comprehensively analyzed the current research progress and found that gut microbiota may affect respiratory system diseases through various pathways, including immune regulation, inflammatory responses, and airway mucus secretion. Additionally, environmental factors, lifestyle, and dietary habits are also closely related to gut microbiota and respiratory system health. Understanding the relationship between gut microbiota and respiratory system diseases not only helps to reveal the mechanisms of disease occurrence but also provides a theoretical basis for the development of new treatment strategies. Future research should focus on exploring the types and functions of gut microbiota, conducting clinical trials based on this, investigating the effects of gut microbiota modulation on the treatment and prevention of respiratory system diseases, and providing new directions for personalized medicine. 展开更多
关键词 Gut microbiota Respiratory system diseases Microbial ecosystem immune regulation Inflammatory response ASTHMA Chronic obstructive pulmonary disease
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The Barrier of the Child and Parent Expected Models for Entering the School System-A Secondary Publication
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作者 Xavier Conus 《Journal of Contemporary Educational Research》 2024年第2期243-255,共13页
The recognition of the positive value of student diversity and their right to full participation are key aspects of inclusion as a means of managing heterogeneity of the school population from an equality perspective.... The recognition of the positive value of student diversity and their right to full participation are key aspects of inclusion as a means of managing heterogeneity of the school population from an equality perspective.As the school cannot welcome the diversity of children without including their families,the same logic needs to apply to the relationship between the school and parents,particularly in the current environment where the school-family partnership appears as a privileged institutional leverage in the fight against inequalities at school.Based on an ethnographical study exploring how the relationship between the school and the families builds up in a Swiss school located in a context of strong cultural diversity,this paper interrogates how the school norm can be the main limitation to the inclusion of students and parents who are unfamiliar with the school.Derived from field observations and interviews,our results show how the teachers tend to approach their relationship with new students and their parents from the standpoint of narrowly defined expected models,leading them to engage in a vain attempt to conform the students and parents when they deviate from these models.The possibility of entering the school system for students and parents unfamiliar with school is hindered by the exclusive and excluding normativity on which the models of the child and the parent expected by the teachers are grounded.Based on these observations,we discuss how an inclusive approach seems to us to require in the first place a necessary process of decentering from the school and teachers,as a condition for recognition of the actual child and parent. 展开更多
关键词 Educational inclusion and exclusion Family and education Norms and regulations Primary and elementary education Switzerland
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Mesenchymal stem cell-derived exosomes regulate microglia phenotypes:a promising treatment for acute central nervous system injury 被引量:8
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作者 Yu-Yan Liu Yun Li +8 位作者 Lu Wang Yan Zhao Rui Yuan Meng-Meng Yang Ying Chen Hao Zhang Fei-Hu Zhou Zhi-Rong Qian Hong-Jun Kang 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第8期1657-1665,共9页
There is growing evidence that long-term central nervous system(CNS)inflammation exacerbates secondary deterioration of brain structures and functions and is one of the major determinants of disease outcome and progre... There is growing evidence that long-term central nervous system(CNS)inflammation exacerbates secondary deterioration of brain structures and functions and is one of the major determinants of disease outcome and progression.In acute CNS injury,brain microglia are among the first cells to respond and play a critical role in neural repair and regeneration.However,microglial activation can also impede CNS repair and amplify tissue damage,and phenotypic transformation may be responsible for this dual role.Mesenchymal stem cell(MSC)-derived exosomes(Exos)are promising therapeutic agents for the treatment of acute CNS injuries due to their immunomodulatory and regenerative properties.MSC-Exos are nanoscale membrane vesicles that are actively released by cells and are used clinically as circulating biomarkers for disease diagnosis and prognosis.MSC-Exos can be neuroprotective in several acute CNS models,including for stroke and traumatic brain injury,showing great clinical potential.This review summarized the classification of acute CNS injury disorders and discussed the prominent role of microglial activation in acute CNS inflammation and the specific role of MSC-Exos in regulating pro-inflammatory microglia in neuroinflammatory repair following acute CNS injury.Finally,this review explored the potential mechanisms and factors associated with MSCExos in modulating the phenotypic balance of microglia,focusing on the interplay between CNS inflammation,the brain,and injury aspects,with an emphasis on potential strategies and therapeutic interventions for improving functional recovery from early CNS inflammation caused by acute CNS injury. 展开更多
关键词 acute CNS injury central nervous system inflammation exosome immune regulation mesenchymal stem cell mesenchymal stem cell-derived exosomes(MSC-Exos) microglia activation microglia phenotypic transformation molecular mechanism neuroinflammation
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Water hammer protection for diversion systems in front of pumps in long-distance water supply projects 被引量:4
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作者 Lin Shi Jian Zhang +3 位作者 Xiao-dong Yu Sheng Chen Wen-long Zhao Xu-yun Chen 《Water Science and Engineering》 EI CAS CSCD 2023年第2期211-218,共8页
For a water supply system with long-distance diversion pipelines, in addition to the water hammer problems that occur beyond pumps, the safety of the water diversion pipeline in front of pumps also deserves attention.... For a water supply system with long-distance diversion pipelines, in addition to the water hammer problems that occur beyond pumps, the safety of the water diversion pipeline in front of pumps also deserves attention. In this study, a water hammer protection scheme combined with an overflow surge tank and a regulating valve was developed. A mathematical model of the overflow surge tank was developed, and an analytical formula for the height of the overflow surge tank was derived. Furthermore, a practical water supply project was used to evaluate the feasibility of the combined protection scheme and analyze the sensitivity of valve regulation rules. The results showed that the combined protection scheme effectively reduced the height of the surge tank, lessened the difficulties related to construction, and reduced the necessary financial investment for the project. The two-stage closing rule articulated as fast first and then slow could minimize the overflow volume of the surge tank when the power failure occurred, while the two-stage opening rule articulated as slow first and then fast could be more conducive to the safety of the water supply system when the pump started up. 展开更多
关键词 Long-distance diversion pipeline Water supply Water hammer Overflow surge tank Regulating valve
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Review of peri-urban agriculture as a regional ecosystem service 被引量:2
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作者 Setyardi Pratika Mulya Heru Purboyo Hidayat Putro Delik Hudalah 《Geography and Sustainability》 CSCD 2023年第3期244-254,共11页
The peri-urban area possesses mixed characteristics of rural and urban areas,i.e.,agricultural,and built-up land.This review explains various themes and concepts of peri-urban areas and the importance of peri-urban ag... The peri-urban area possesses mixed characteristics of rural and urban areas,i.e.,agricultural,and built-up land.This review explains various themes and concepts of peri-urban areas and the importance of peri-urban agriculture(PUA)as an ecosystem service(ES)for their surrounding areas.The methodological approach is a systematic literature search and explanatory review of books and journal articles.The focus of the discussion is as follows:(1)quantification of review results,(2)urbanization pressures,peri-urban,and governance,(3)two different concepts about the peri-urban area,(4)protection of PUA and their resilience,and(5)role of PUA in providing ESs to other regions.The review shows that PUA is more crucial in urban areas than in rural areas in terms of food supply,ecology and biodiversity preservation,disaster mitigation,and recreation.One of the primary causes of PUA loss is massive urban expansion,which entails the conversion of agricultural land in peri-urban areas into built-up land.Hence,we suggest that every country should develop a peri-urban management policy.We argue that sociocultural biases in PUA have resulted in many institutional constraints on peri-urban management being incorporated within existing political and regulatory frameworks,including planning practices and longstanding laws and regulations. 展开更多
关键词 FARMING Impact REGULATION URBANIZATION Urban-rural interaction
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Cross-kingdom regulation by plant-derived miRNAs in mammalian systems 被引量:1
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作者 Linpu Yang Han Feng 《Animal Models and Experimental Medicine》 CAS CSCD 2023年第6期518-525,共8页
MicroRNAs(miRNAs)are small noncoding RNA molecules ubiquitously distributed across diverse organisms,serving as pivotal regulators of genetic expression.Notably,plant-derived miRNAs have been demonstrated to have uniq... MicroRNAs(miRNAs)are small noncoding RNA molecules ubiquitously distributed across diverse organisms,serving as pivotal regulators of genetic expression.Notably,plant-derived miRNAs have been demonstrated to have unique bioactivity and certain stability in mammalian systems,thereby facilitating their capacity for cross-kingdom modulation of gene expression.While there is substantial evidence supporting the regulation of mammalian cells by plant-derived miRNAs,several questions remain unanswered.Specifically,a comprehensive investigation of the mechanisms underlying the stability and transport of plant miRNAs and their cross-kingdom regulation of gene expression in mammals remains to be done.In this review,we summarized the origin,processing,and functional mechanisms of plant miRNAs in mammalian tissues and circulation,emphasizing their greater resistance to mammalian digestion and circulation systems compared to animal miRNAs.Additionally,we introduce four well-known plant miRNAs that have been extensively studied for their functions and mechanisms in mammalian systems.By delving into these aspects,we aim to offer a fundamental understanding of this intriguing field and shed light on the complex interactions between plant miRNAs and mammalian biology. 展开更多
关键词 cross-kingdom REGULATION plant-derived microRNAs
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Computing of LQR Technique for Nonlinear System Using Local Approximation 被引量:1
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作者 Aamir Shahzad Ali Altalbe 《Computer Systems Science & Engineering》 SCIE EI 2023年第7期853-871,共19页
The main idea behind the present research is to design a state-feedback controller for an underactuated nonlinear rotary inverted pendulum module by employing the linear quadratic regulator(LQR)technique using local a... The main idea behind the present research is to design a state-feedback controller for an underactuated nonlinear rotary inverted pendulum module by employing the linear quadratic regulator(LQR)technique using local approximation.The LQR is an excellent method for developing a controller for nonlinear systems.It provides optimal feedback to make the closed-loop system robust and stable,rejecting external disturbances.Model-based optimal controller for a nonlinear system such as a rotatory inverted pendulum has not been designed and implemented using Newton-Euler,Lagrange method,and local approximation.Therefore,implementing LQR to an underactuated nonlinear system was vital to design a stable controller.A mathematical model has been developed for the controller design by utilizing the Newton-Euler,Lagrange method.The nonlinear model has been linearized around an equilibrium point.Linear and nonlinear models have been compared to find the range in which linear and nonlinear models’behaviour is similar.MATLAB LQR function and system dynamics have been used to estimate the controller parameters.For the performance evaluation of the designed controller,Simulink has been used.Linear and nonlinear models have been simulated along with the designed controller.Simulations have been performed for the designed controller over the linear and nonlinear system under different conditions through varying system variables.The results show that the system is stable and robust enough to act against external disturbances.The controller maintains the rotary inverted pendulum in an upright position and rejects disruptions like falling under gravitational force or any external disturbance by adjusting the rotation of the horizontal link in both linear and nonlinear environments in a specific range.The controller has been practically designed and implemented.It is vivid from the results that the controller is robust enough to reject the disturbances in milliseconds and keeps the pendulum arm deflection angle to zero degrees. 展开更多
关键词 COMPUTING rotary inverted pendulum(RIP) modeling and simulation linear quadratic regulator(LQR) nonlinear system
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Robust output regulation problem with prescribed performance for nonlinear strict feedback systems
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作者 ZHU Haichao LAN Weiyao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第4期1033-1041,共9页
This paper investigates the problem of robust output regulation control with prospected transient property for strict feedback systems.By employing the internal model principle,the robust output regulation problem wit... This paper investigates the problem of robust output regulation control with prospected transient property for strict feedback systems.By employing the internal model principle,the robust output regulation problem with a prospected property can be transformed to a robust stabilization problem with a new output constraint.Then,by constructing the speed function and adopting barrier Lyapunov function technique,the dynamic feedback controller can be designed not only to drive error output of the closed-loop system entering into a prescribed performance bound within a given finite time,but also to achieve that the error output converges to zero asymptotically.The effectiveness of the results is illustrated by a simulation example. 展开更多
关键词 robust output regulation nonlinear system prescribed performance bound speed function finite time
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Analysing Various Control Techniques for Manipulator Robotic System (Robogymnast)
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作者 Mahmoud Mohamed Bdereddin Abdul Samad +2 位作者 Fatih Anayi Michael Packianather Khalid Yahya 《Computers, Materials & Continua》 SCIE EI 2023年第6期4681-4696,共16页
The Robogymnast is a highly complex,three-link system based on the triple-inverted pendulum and is modelled on the human example of a gymnast suspended by their hands from the high bar and executing larger and larger ... The Robogymnast is a highly complex,three-link system based on the triple-inverted pendulum and is modelled on the human example of a gymnast suspended by their hands from the high bar and executing larger and larger upswings to eventually rotate fully.The links of the Robogymnast correspond respectively to the arms,trunk,and lower limbs of the gymnast,and from its three joints,one is under passive operation,while the remaining two are powered.The passive top joint poses severe challenges in attaining the smooth movement control needed to operate the Robogymnast effectively.This study assesses four types of controllers used for systems operation and identifies how far response stabilisation is achieved with each.The system is simulated using MATLAB Simulink,with findings generated regarding rising and settling time,as well as overshoot.The research primarily seeks to exam-ine the application of a linear quadratic regulator controller,proportional-integral-derivative controller,fuzzy linear quadratic regulator controller and linear quadratic regulator-proportional-integral-derivative controller for this type of system and comparisons between the different controllers to demon-strate successful performance,which highlights the claimed advantages of the proposed system. 展开更多
关键词 Robot gymnast(Robogymnast) proportional-integral-derivative(PID) linear quadratic regulator(LQR) fuzzy linear quadratic regulator(FLQR) Acrobat Robot(Acrobat)
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Tree-based ecosystem services supply and multifunctionality of church forests and their agricultural matrix near Lake Tana,Ethiopia
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作者 Ferehiwot Mequanint Tobias Fremout +7 位作者 Diederik Strubbe Alemayehu Wassie Shimelis Aynalem Enyew Adgo Jan Nyssen Amaury Frankl Luc Lens Bart Muys 《Forest Ecosystems》 SCIE CSCD 2023年第6期656-667,共12页
Ecosystem services(ES)are the connection between nature and society,and are essential for the well-being of local communities that depend on them.In Ethiopia,church forests and the surrounding agricultural matrix supp... Ecosystem services(ES)are the connection between nature and society,and are essential for the well-being of local communities that depend on them.In Ethiopia,church forests and the surrounding agricultural matrix supply numerous ES.However,the ES delivered by both land use types have not yet been assessed simultaneously.Here we surveyed both church forests and their agricultural matrices,aiming to quantify,compare and unravel the drivers underlying tree-based ES supply,density and multifunctionality.We found that almost all church forests and half of the agricultural matrices provided high ES densities.ES multifunctionality was higher in the agricultural matrices,suggesting that people deliberately conserve or plant multifunctional tree species.Furthermore,the supply of all categories of ES was positively correlated with church forest age(p-value<0.001)in the agricultural matrix,while the extent of church forest was positively correlated with the density of all categories ecosystem services score in the church forests(p-value<0.001).Our results can be used to prioritize conservation efforts at sites that provide high levels of ES supply,ES density and ES multifunctionality,and to prioritize restoration efforts at sites with low levels thereof. 展开更多
关键词 Church forest Remnant forest Provisioning service Regulating service Cultural service Multifunctionality Key informant interview Agricultural matrix
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Boosted urea electro-oxidation over Ni_(3)N-based nanocomposite via systematic regulation tactic
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作者 Ping Li Yuqi Huang +2 位作者 Quhua Huang Wenqin Li Shuanghong Tian 《Journal of Energy Chemistry》 SCIE EI CSCD 2023年第12期479-490,I0013,共13页
Exploiting high-efficiency Ni-based materials for electrocatalytic urea oxidation reaction(UOR) is critical for urea-related technologies.The catalytic site density,intrinsic activity,charge transfer,and mass diffusio... Exploiting high-efficiency Ni-based materials for electrocatalytic urea oxidation reaction(UOR) is critical for urea-related technologies.The catalytic site density,intrinsic activity,charge transfer,and mass diffusion determine overall electrocatalytic efficiency.Simultaneous modulation over the above four factors promises advanced electrocatalysis,yet challenging.Herein we propose a systematic regulation tactic over composition and geometric structure,constructing a nanocomposite comprising Mn doped Ni_(3)N nanoparticles anchored on reduced graphene oxide(rGO/Mn-Ni_(3)N),achieving elegant integration of four design principles into one,thereby eminently boosting UOR.Particularly,Mn doping in Ni_(3)N can modulate electronic state to induce intrinsic activity regulation.Combining metallic Mn-Ni_(3)N with rGO to engineer hierarchical architecture not only promotes charge transfer,but also enriches active site population.Intriguingly,improved hydrophilicity could impart better electrolyte penetration and gas escape.Consequently,such system-optimized rGO/Mn-Ni_(3)N demonstrates state-of-the-art-level UOR electrocatalysis.This work offers a novel paradigm to create advanced catalysts via systematic and integrated modulation. 展开更多
关键词 Ni_(3)N Geometric structure Composition engineering systematic regulation Urea oxidation
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Determination of AVR System PID Controller Parameters Using Improved Variants of Reptile Search Algorithm and a Novel Objective Function
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作者 Baran Hekimoglu 《Energy Engineering》 EI 2023年第7期1515-1540,共26页
Two novel improved variants of reptile search algorithm(RSA),RSA with opposition-based learning(ORSA)and hybrid ORSA with pattern search(ORSAPS),are proposed to determine the proportional,integral,and derivative(PID)c... Two novel improved variants of reptile search algorithm(RSA),RSA with opposition-based learning(ORSA)and hybrid ORSA with pattern search(ORSAPS),are proposed to determine the proportional,integral,and derivative(PID)controller parameters of an automatic voltage regulator(AVR)system using a novel objective function with augmented flexibility.In the proposed algorithms,the opposition-based learning technique improves the global search abilities of the original RSA algorithm,while the hybridization with the pattern search(PS)algorithm improves the local search abilities.Both algorithms are compared with the original RSA algorithm and have shown to be highly effective algorithms for tuning the PID controller parameters of an AVR system by getting superior results.Several analyses such as transient,stability,robustness,disturbance rejection,and trajectory tracking are conducted to test the performance of the proposed algorithms,which have validated the good promise of the proposed methods for controller designs.The performances of the proposed design approaches are also compared with the previously reported PID controller parameter tuning approaches to assess their success.It is shown that both proposed approaches obtain excellent and robust results among all compared ones.That is,with the adjustment of the weight factorα,which is introduced by the proposed objective function,for a system with high bandwitdh(α=1),the proposed ORSAPS-PID system has 2.08%more bandwidth than the proposed ORSA-PID system and 5.1%faster than the fastest algorithm from the literature.On the other hand,for a system where high phase and gain margins are desired(α=10),the proposed ORSA-PID system has 0.53%more phase margin and 2.18%more gain margin than the proposed ORSAPS-PID system and has 0.71%more phase margin and 2.25%more gain margin than the best performing algorithm from the literature. 展开更多
关键词 Reptile search algorithm pattern search multidirectional search metaheuristics automatic voltage regulator optimal PID controller
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The Mitigation Strategies for Managing the Potential Environmental Risks Posed by Oil and Gas Development on Mangrove Ecosystems in the Coastal Communities
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作者 Collin Augustus Henry Thomas B. Singh Temitope D. Timothy Oyedotun 《Journal of Geoscience and Environment Protection》 2023年第5期243-268,共26页
Guyana is an oil-producing country vulnerable to potential oil spills and the environmental risks posed by oil and gas exploration and production activities. Despite the technologically advanced equipment employed by ... Guyana is an oil-producing country vulnerable to potential oil spills and the environmental risks posed by oil and gas exploration and production activities. Despite the technologically advanced equipment employed by ExxonMobil Guyana and affiliates, an oil spill could occur due to accidents, equipment failures, or sabotages. The selected coastal communities as the study areas in Region 1 and Region 2 could be adversely affected, particularly the mangrove ecosystems. Potential oil spill pollution will adversely impact mangrove ecosystems in Region 1 and Region 2. Mangroves offer significant benefits to coastal communities, such as coastal defence and carbon sequestration, which puts Guyana on the world map. The research aimed to investigate the mitigation strategies to manage the potential environmental risks on mangrove ecosystems in the coastal communities of Region 1 and Region 2. It followed a qualitative approach and conducted semi-structured interviews with the Toshaos of the selected coastal communities. The data analysis strategy was thematic analysis using the Nvivo software. The major themes included legal and policy frameworks, oil spill response strategies, community-based involvement, and monitoring and enforcement of regulations. The significant results included reviewing and updating the regulatory framework for mangrove management and conservation;oil spills mitigation measures such as containment and shoreline protection and cleanup, cost recovery and compensation, and limited monitoring and law enforcement of mangrove management and conservation regulations by inter-agencies. The regulatory and institutional framework is outdated and needs to be amended. The agencies overseeing mangrove management and conservation have overlapping responsibilities and require more coordination. There should be greater collaboration among agencies for mangrove management and conservation and improved monitoring and enforcement programmes through institutional support. 展开更多
关键词 ENFORCEMENT Monitoring Oil Spill POLICY REGULATION
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