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技术革新与传统工艺的交汇:Taylor全新Action Control琴颈技术有何意义与影响?
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作者 Acoustic Soul原声之魂 《乐器》 2025年第6期112-113,共2页
自1974年由Bob Taylor与Kurt Listug在美国加州创立以来,Taylor Guitars便以其精密的工艺与技术驱动的设计理念在全球吉他制造领域中脱颖而出。与其同时代品牌Martin不同,Taylor从一开始便不以复刻古典工艺为目标,而是试图为现代演奏者... 自1974年由Bob Taylor与Kurt Listug在美国加州创立以来,Taylor Guitars便以其精密的工艺与技术驱动的设计理念在全球吉他制造领域中脱颖而出。与其同时代品牌Martin不同,Taylor从一开始便不以复刻古典工艺为目标,而是试图为现代演奏者提供更精准、更便捷、更高适应性的演奏工具。Taylor的品牌理念可以总结为“以技术回应音乐性”。 展开更多
关键词 action control琴颈技术 Taylor Guitars
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The Immunomodulatory,Anti-Tumor,and Metabolic Regulatory Effects of Fraction D of Polysaccharide from Grifola frondosa:Clinical Experiments and Mechanistic Insights
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作者 Nurfarih Hanna Mohd Zarif Fikri Bin Mohd +1 位作者 Muhammad Nabil Fikri Bin Mohd Nurfarazuna Binti Mohd Fadrol 《Proceedings of Anticancer Research》 2026年第1期84-93,共10页
Grifola frondosa(Maitake)is traditionally valued for its health benefits,with polysaccharides being key bioactive components.This paper investigates a specific subfraction,Fraction D(GFP-D),evaluating its clinical eff... Grifola frondosa(Maitake)is traditionally valued for its health benefits,with polysaccharides being key bioactive components.This paper investigates a specific subfraction,Fraction D(GFP-D),evaluating its clinical effects and mechanisms in immune enhancement,adjunctive anti-tumor activity,and regulation of glucose/lipid metabolism.Three clinical trials were conducted.In an immune study,120 healthy volunteers(CD4+T cell count 500–1000 cells/μL)received 150 mg/day GFP-D for 8 weeks,resulting in significant increases in CD4+T cells(from 632±95 to 812±108 cells/μL,28.5%increase,within the physiological activation range),CD4+/CD8+ratio,NK cell activity,IL-2,and IFN-γ(all P<0.001 vs.placebo).An anti-tumor study with 80 advanced cancer patients(stratified by age,tumor stage,and histotype)showed that adding 1000 mg/day GFP-D to chemotherapy improved objective response rate(52.5%vs.30.0%,P=0.036,95%CI:1.02–3.87),one-year progression-free survival(55.8%vs.33.3%,P=0.022),and preserved immune parameters versus chemotherapy alone.A metabolic study in 90 type 2 diabetes patients found that 400 mg/day GFP-D for 12 weeks significantly lowered fasting glucose,HbA1c,total cholesterol,triglycerides,and LDL-C,while raising HDL-C(from 1.0±0.2 to 1.2±0.2 mmol/L,20%increase,supported by increased AMPK phosphorylation).Mechanistically,immune enhancement involves macrophage/dendritic cell activation via Dectin-1/TLR4 receptors(confirmed by increased receptor expression and downstream signaling molecules),promoting cytokine-driven T/NK cell responses.Anti-tumor effects stem from immunomodulation,direct induction of cancer cell apoptosis(via mitochondrial/caspase pathways,verified by increased Bax/Bcl-2 ratio and caspase-3 activation),and angiogenesis inhibition by downregulating VEGF.Metabolic benefits are linked to AMPK pathway activation in liver/muscle(confirmed by increased p-AMPK/AMPK ratio),enhancing glucose uptake and inhibiting gluconeogenesis/lipogenesis,alongside modulation of gut microbiota(increased Bifidobacterium and Lactobacillus abundance).All trials reported no severe adverse events related to GFP-D;liver/kidney function parameters(ALT,AST,creatinine,urea nitrogen)remained within normal ranges throughout the intervention.Collectively,GFP-D emerges as a multi-functional bioactive agent with substantial therapeutic potential. 展开更多
关键词 Grifola frondosa Maitake polysaccharide Fraction D Immune modulation Adjunctive cancer therapy Glycemic control Lipid metabolism Clinical trial Mechanism of action
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Action Control of Soccer Robots Based on Simulated Human Intelligence
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作者 Tie-Jun Li Gui-Qiang Chen Gui-Fang Shao 《International Journal of Automation and computing》 EI 2010年第1期55-63,共9页
A multi-modal action control approach is proposed for an autonomous soccer robot when the bottom hardware is unchangeable. Different from existing methods, the proposed control approach defines actions with the princi... A multi-modal action control approach is proposed for an autonomous soccer robot when the bottom hardware is unchangeable. Different from existing methods, the proposed control approach defines actions with the principle of "perception-planning-action" inspired by human intelligence. Character extraction is used to divide the perception input into different modes. Different control modes are built by combining different control methods for the linear velocity and angular velocity. Based on production rules, the motion control is realized by connecting different perceptions to the corresponding control mode. Simulation and real experiments are conducted with the middle-sized robot Frontier-I, and the proposed method is compared with a proportional-integral-derivative (PID) control method to display its feasibility and performance. The results show that the multi-modal action control method can make robots react rapidly in a dynamic environment. 展开更多
关键词 Intelligent control artificial intelligence PID control PERCEPTION action control ROBOTS
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Application of Statistical Process Control for Setting Action Thresholds as Quality Assurance of Dose Verifications in External Beam Radiotherapy
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作者 Philip Kioko Ndonye Samuel Nii Adu Tagoe 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2022年第1期22-35,共14页
Purpose: To test the concept of Statistical Process Control (SPC) as a Quality Assurance (QA) procedure for dose verifications in external beam radiation therapy in conventional and 3D Conformal Radiotherapy (3D-CRT) ... Purpose: To test the concept of Statistical Process Control (SPC) as a Quality Assurance (QA) procedure for dose verifications in external beam radiation therapy in conventional and 3D Conformal Radiotherapy (3D-CRT) treatment of cervical cancer. Materials and Methods: A study of QA verification of target doses of 198 cervical cancer patients undergoing External Beam Radiotherapy (EBRT) treatments at two different cancer treatment centers in Kenya was conducted. The target doses were determined from measured entrance doses by the diode in vivo dosimetry. Process Behavior Charts (PBC) developed by SPC were applied for setting Action Thresholds (AT) on the target doses. The AT set was then proposed as QA limits for acceptance or rejection of verified target doses overtime of the EBRT process. Result and Discussion: Target doses for the 198 patients were calculated and SPC applied to test whether the action limits set by the Process Behavior Charts could be applied as QA for verified doses in EBRT. Results for the two sub-groups of n = 3 and n = 4 that were tested produced action thresholds which are within clinical dose specifications for both conventional AP/PA and 3D-CRT EBRT treatment techniques for cervical cancer. Conclusion: Action thresholds set by SPC were within the clinical dose specification of ±5% uncertainty for both conventional AP/PA and 3D-CRT EBRT treatment techniques for cervical cancer. So the concept of SPC could be applied in setting QA action limits for dose verifications in EBRT. 展开更多
关键词 Quality Assurance Statistical Process control action Thresholds Dose Verification External Beam Radiation Therapy
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On the Generalization of Integrator and Integral Control Action
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作者 Baishun Liu 《International Journal of Modern Nonlinear Theory and Application》 2014年第2期44-52,共9页
This paper provides a solution to generalize the integrator and the integral control action. It is achieved by defining two function sets to generalize the integrator and the integral control action, respectively, res... This paper provides a solution to generalize the integrator and the integral control action. It is achieved by defining two function sets to generalize the integrator and the integral control action, respectively, resorting to a stabilizing controller and adopting Lyapunov method to analyze the stability of the closed-loop system. By originating a powerful Lyapunov function, a universal theorem to ensure regionally as well as semi-globally asymptotic stability is established by some bounded information. Consequently, the justification of two propositions on the generalization of integrator and integral control action is verified. Moreover, the conditions used to define the function sets can be viewed as a class of sufficient conditions to design the integrator and the integral control action, respectively. 展开更多
关键词 GENERAL INTEGRAL control Nonlinear control GENERAL INTEGRATOR GENERAL INTEGRAL action SUFFICIENT Condition LYAPUNOV Function Output Regulation
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The Effect of Procrastination on Physical Exercise among College Students—The Chain Effect of Exercise Commitment and Action Control
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作者 Wenjuan Zhang Menglin Xu +2 位作者 Yujuan Feng Zhixiong Mao Zengyin Yan 《International Journal of Mental Health Promotion》 2024年第8期611-622,共12页
Background:Exercise procrastination is prevalent among college students,causing decline in physical fitness.It is imperative to investigate the mechanism affecting college students’physical activity behaviors.This st... Background:Exercise procrastination is prevalent among college students,causing decline in physical fitness.It is imperative to investigate the mechanism affecting college students’physical activity behaviors.This study was aimed at investigating the effect of procrastination on college students’physical exercise behavior,and the chain mediation effects of exercise commitment and action control(AC),to provide a theoretical basis for interventions targeting physical exercise behavior among college students.Methods:A questionnaire survey was conducted using convenience sampling.The General Procrastination Scale,Exercise Commitment Scale,Action Control Scale,and Physical Activity Rating Scale-3 questionnaires were used.Participants were 581 college students(age 19.27±0.94 years;243 males and 338 females).Statistical methods of regression analysis and structural equation modeling(SEM)were applied.Results:Procrastination,exercise commitment,and action control were found to be significant predictors of physical exercise behavior.Among these predictors,exercise commitment and action control showed full mediation effects in the relationship between procrastination and physical exercise behavior,and explained 25.48%and 30.77%of the total variance,respectively.The chain mediation effect of exercise commitment-action control was significant,accounting for 22.60%of the total variance,and the total indirect effect was 79.33%.Conclusion:Therefore,higher procrastination was associated with less participation in physical exercise behavior among college students.Improvements in exercise commitment and volitional decision-making ability for physical exercise behavior promoted physical exercise behavior,and increased exercise commitment promoted volitional decision-making ability among the students.The chain reaction effect of exercise commitment and action control also buffered the negative effects of procrastination on physical exercise behavior,thereby increasing physical exercise behavior among college students. 展开更多
关键词 College student PROCRASTINATION exercise commitment action control exercise behavior chain intermediary
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Self-Triggered Impulsive Control for Nonlinear Stochastic Systems
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作者 Tao Zhan Yi Ji +2 位作者 Yabin Gao Hongyi Li Yuanqing Xia 《IEEE/CAA Journal of Automatica Sinica》 2025年第1期264-266,共3页
Dear Editor,This letter deals with the stabilization problem of nonlinear stochastic systems via self-triggered impulsive control(STIC), where the timing of impulsive control actions is not dependent on continuous sta... Dear Editor,This letter deals with the stabilization problem of nonlinear stochastic systems via self-triggered impulsive control(STIC), where the timing of impulsive control actions is not dependent on continuous state monitoring. In contrast to the existing self-triggered control method, novel self-triggered mechanism(STM) is proposed by incorporating a waiting time for stabilizing impulses. This allows for direct prediction of the next impulsive instant. 展开更多
关键词 direct prediction next impulsive instant impulsive control stabilization problem nonlinear stochastic systems impulsive control actions self triggered control state monitoring STABILIZATION
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Stress field evolution mechanism and regional stress control technology of deep mining roadway
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作者 ZUO Jian-ping ZHU Fan +1 位作者 MA Zong-yu XU Cheng-yi 《Journal of Central South University》 2025年第10期3927-3944,共18页
Aiming at the problem that the distance between the main roadway and the working face in Hudi Coal Industry Panel was more than 100 m,which was still affected by mining,high stress concentration of the roadway,and dif... Aiming at the problem that the distance between the main roadway and the working face in Hudi Coal Industry Panel was more than 100 m,which was still affected by mining,high stress concentration of the roadway,and difficulty of supporting overall convergence of the section,the mechanical characteristics of the core bearing strata of the overlying rock caving in the working face were studied.The correlation mechanism between the overlying rock caving and the deformation and failure of the roadway was analyzed,and the quantitative evaluation index was established to comprehensively analyze different influencing factors.Based on the key strata theory,the mechanical difference transfer model of working face mining and panel roadway deformation and failure was established.It was considered that the difference in fracture morphology was the key to the far-field stress disturbance.The regional stress control technology was proposed to block or reduce the stress transfer,so that the peak stress of the panel main roadway was reduced,and the deformation of the surrounding rock was significantly reduced,which provides a reference value for the roadway support with serious influence of mining roadway. 展开更多
关键词 spatial structural instability of overburden rock differentiated stress concentration body regional stress control roof cutting and pressure relief mining stress transmission and action
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多过程行动控制框架在身体活动领域中的应用进展
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作者 朱佳佳 金泓丞 +3 位作者 蒋伟红 陈梦怡 李佳佳 诸纪华 《护理研究》 北大核心 2026年第1期170-176,共7页
综述多过程行动控制(multi-process action control,M-PAC)框架的起源、发展及其在身体活动领域研究中的应用,分析该框架在促进身体活动行为启动与维持中的作用。通过探讨M-PAC框架的核心过程及其相互关系,旨在为推动身体活动干预策略... 综述多过程行动控制(multi-process action control,M-PAC)框架的起源、发展及其在身体活动领域研究中的应用,分析该框架在促进身体活动行为启动与维持中的作用。通过探讨M-PAC框架的核心过程及其相互关系,旨在为推动身体活动干预策略的精准化与持续性提供理论依据和实践指导。 展开更多
关键词 多过程行动控制 身体活动 行为改变 理论模型 综述
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线粒体质量控制系统在类风湿关节炎中作用机制的研究概况
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作者 刘菲菲 汪元 +1 位作者 刘健 曹周芳 《中医药临床杂志》 2026年第1期186-192,共7页
类风湿关节炎(RA)是一种全身性、慢性、炎症性疾病,发病机制尚不清楚,其病情复杂多变,严重影响了患者的生活质量。线粒体作为细胞的动力中心,起到能量转换、代谢调节和控制细胞凋亡等作用。有研究表明,线粒体质量控制系统包括线粒体氧... 类风湿关节炎(RA)是一种全身性、慢性、炎症性疾病,发病机制尚不清楚,其病情复杂多变,严重影响了患者的生活质量。线粒体作为细胞的动力中心,起到能量转换、代谢调节和控制细胞凋亡等作用。有研究表明,线粒体质量控制系统包括线粒体氧化应激、动力学、凋亡、自噬、生物发生和钙稳态等环节,参与RA病程的进展。因此,文章综述着重于探讨线粒体质量控制系统在RA发生发展中的作用途径,以期明确线粒体在RA中的发病机制,同时发现如何有效调控线粒体功能,找到相应的治疗靶点,可能为RA的治疗提供借鉴和理论依据。 展开更多
关键词 线粒体质量控制 类风湿关节炎 作用机制 研究进展
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多层厚硬顶板大采高综放面强矿压特征及防控技术
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作者 张震 《中国煤炭》 北大核心 2026年第1期22-35,共14页
为解决榆神矿区多层厚硬顶板大采高综放面开采期间强矿压带来的支架压架、立柱受冲击严重损坏的难题,采用压力传感器和位移传感器对曹家滩煤矿122108大采高综放开采面进行系统性监测,明确了多层厚硬顶板大采高综放面矿压显现宏观特征,... 为解决榆神矿区多层厚硬顶板大采高综放面开采期间强矿压带来的支架压架、立柱受冲击严重损坏的难题,采用压力传感器和位移传感器对曹家滩煤矿122108大采高综放开采面进行系统性监测,明确了多层厚硬顶板大采高综放面矿压显现宏观特征,分析了多层厚硬顶板覆岩破断动载冲击特征,明确了矿压作用机理,提出了以弱化中低层位岩层、增大充填空间、缩小高层位顶板的活动空间为目标的井下水力区域压裂顶板弱化技术。研究结果表明,多层厚硬顶板大采高综放面矿压显现异常强烈,表现为来压步距大、持续时间长、动载系数高、支架大幅下缩的特点,工作面平均周期来压步距18.4 m,来压持续距离11.5 m,来压平均动载系数1.45,支架下缩量聚集于0.4~1.0 m;多层厚硬顶板大采高综放面来压呈现出强动载来压期间多次连续性或短距间断性大周期来压的新特征,煤层上覆100 m范围内中高位厚硬岩层破断失稳对工作面具有较强的冲击作用,随厚硬岩层距煤层距离继续增加,其周期破断不再对工作面产生矿压作用,下位厚硬岩层的破断一定程度上加速了上位顶板断裂;井下水力区域压裂顶板弱化技术有效减缓了工作面的强矿压显现,压裂后周期来压步距最大值由64 m降至35 m,工作面平均周期来压持续距离由11.5 m降至8.4 m,来压动载系数1.4以上的比例由85.27%降至9.80%,能量104 J以上微震事件个数下降54.02%。 展开更多
关键词 多层厚硬顶板 矿压显现特征 水力区域压裂顶板弱化技术 矿压作用机理 围岩控制
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超长混凝土结构温度作用分析及裂缝控制措施
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作者 范小周 林志海 张建劭 《建筑技术》 2026年第1期59-63,共5页
以某超长教学楼建筑为例,对其温度作用计算过程进行了系统阐述,在温度作用计算中,应计入混凝土收缩当量温差。本研究采用midas Gen软件进行了有限元分析,分析模型特别考虑了桩基础刚度的影响,基于计算结果,提出楼板配筋应考虑温度应力,... 以某超长教学楼建筑为例,对其温度作用计算过程进行了系统阐述,在温度作用计算中,应计入混凝土收缩当量温差。本研究采用midas Gen软件进行了有限元分析,分析模型特别考虑了桩基础刚度的影响,基于计算结果,提出楼板配筋应考虑温度应力,对易发生应力集中区域应采取进一步构造加强措施,同时对端部两跨的竖向构件应适当加强配筋,提高其延性;此外,本研究还基于温度作用的有限元计算结果,针对性地提出了设计与施工两阶段的裂缝控制措施,可为同类型混凝土结构的工程实践提供技术参考。 展开更多
关键词 超长混凝土结构 温度作用 收缩当量温差 基础刚度 裂缝控制措施
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意志的外在表现和内在表征的分离
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作者 罗霄骁 周晓林 《心理科学进展》 北大核心 2026年第1期1-17,共17页
意志是自主控制自身的能力,是人类区分于动物和机器的核心特征,是身心健康和社会秩序的基石。其外在表现是主动动作,内在表征是控制信念。前者指基于自身意愿产生的动作;后者指相信主动动作的实施能对外界事物产生影响的信念。前人研究... 意志是自主控制自身的能力,是人类区分于动物和机器的核心特征,是身心健康和社会秩序的基石。其外在表现是主动动作,内在表征是控制信念。前者指基于自身意愿产生的动作;后者指相信主动动作的实施能对外界事物产生影响的信念。前人研究大多基于主动动作研究意志,而个体实施主动动作的同时会持有控制信念。因此,相关研究混淆了意志的外在表现和内在表征。本研究拟基于意志促进表现(volition-motivated performance,VMP)范式,通过分离主动动作和控制信念,结合计算建模、多模态神经影像技术(肌电图/脑电图/功能磁共振成像),系统揭示二者的共享与特异性认知神经机制。据此提出“人类意志过程的双路径假设”:一是主动动作相关路径,体现意志的动作属性;二是控制信念相关路径,体现意志的动机属性。 展开更多
关键词 意志 主动动作 控制信念 自主选择 意志促进表现范式
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Analytic optimal pose tracking control in close-range proximity operations with a non-cooperative target 被引量:1
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作者 Caisheng WEI Guanhua HUANG +1 位作者 Zeyang YIN Qifeng CHEN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第5期410-425,共16页
This paper investigates an analytical optimal pose tracking control problem for chaser spacecraft during the close-range proximity operations with a non-cooperative space target subject to attitude tumbling and unknow... This paper investigates an analytical optimal pose tracking control problem for chaser spacecraft during the close-range proximity operations with a non-cooperative space target subject to attitude tumbling and unknown orbital maneuvering.Firstly,the relative translational motion between the orbital target and the chaser spacecraft is described in the Line-of-Sight(LOS)coordinate frame along with attitude quaternion dynamics.Then,based on the coupled 6-Degree of Freedom(DOF)pose dynamic model,an analytical optimal control action consisting of constrained optimal control value,application time and its duration are proposed via exploring the iterative sequential action control algorithm.Meanwhile,the global closed-loop asymptotic stability of the proposed predictive control action is presented and discussed.Compared with traditional proximity control schemes,the highlighting advantages are that the application time and duration of the devised controller is applied discretely in light of the influence of the instantaneous pose configuration on the pose tracking performance with less energy consumptions rather than at each sample time.Finally,three groups of illustrative examples are organized to validate the effectiveness of the proposed analytical optimal pose tracking control scheme. 展开更多
关键词 Optimal control Close-range proximity operation Non-cooperative space target Coupled attitude and orbit control Iterative sequential action control
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Hybrid Q-learning for data-based optimal control of non-linear switching system 被引量:1
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作者 LI Xiaofeng DONG Lu SUN Changyin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第5期1186-1194,共9页
In this paper,the optimal control of non-linear switching system is investigated without knowing the system dynamics.First,the Hamilton-Jacobi-Bellman(HJB)equation is derived with the consideration of hybrid action sp... In this paper,the optimal control of non-linear switching system is investigated without knowing the system dynamics.First,the Hamilton-Jacobi-Bellman(HJB)equation is derived with the consideration of hybrid action space.Then,a novel data-based hybrid Q-learning(HQL)algorithm is proposed to find the optimal solution in an iterative manner.In addition,the theoretical analysis is provided to illustrate the convergence and optimality of the proposed algorithm.Finally,the algorithm is implemented with the actor-critic(AC)structure,and two linear-in-parameter neural networks are utilized to approximate the functions.Simulation results validate the effectiveness of the data-driven method. 展开更多
关键词 switching system hybrid action space optimal control reinforcement learning hybrid Q-learning(HQL)
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Glucagon-like peptide-1 receptor agonists:Exploring the mechanisms from glycemic control to treatment of multisystemic diseases 被引量:2
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作者 Mo-Wei Kong Yang Yu +2 位作者 Ying Wan Yu Gao Chun-Xiang Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第36期4036-4043,共8页
This editorial takes a deeper look at the insights provided by Soresi and Giannitrapani,which examined the therapeutic potential of glucagon-like peptide-1 receptor agonists(GLP-1RAs)for metabolic dysfunction-associat... This editorial takes a deeper look at the insights provided by Soresi and Giannitrapani,which examined the therapeutic potential of glucagon-like peptide-1 receptor agonists(GLP-1RAs)for metabolic dysfunction-associated fatty liver disease.We provide supplementary insights to their research,highlighting the broader systemic implications of GLP-1RAs,synthesizing the current understanding of their mechanisms and the trajectory of research in this field.GLP-1RAs are revolutionizing the treatment of type 2 diabetes mellitus and beyond.Beyond glycemic control,GLP-1RAs demonstrate cardiovascular and renal protective effects,offering potential in managing diabetic kidney disease alongside renin–angiotensin–aldosterone system inhibitors.Their role in bone metabolism hints at benefits for diabetic osteoporosis,while the neuroprotective properties of GLP-1RAs show promise in Alzheimer's disease treatment by modulating neuronal insulin signaling.Additionally,they improve hormonal and metabolic profiles in polycystic ovary syndrome.This editorial highlights the multifaceted mechanisms of GLP-1RAs,emphasizing the need for ongoing research to fully realize their therapeutic potential across a range of multisystemic diseases. 展开更多
关键词 Glucagon-like peptide-1 receptor agonists Glycemic control Multisystem diseases Mechanism of action Cardiovascular protection Renal disease Bone metabolism Non-alcoholic fatty liver disease NEUROPROTECTION Polycystic ovary syndrome
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Characteristics of mining gas channel expansion in the remote overlying strata and its control of gas flow 被引量:1
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作者 Liu Hongyong Cheng Yuanping +2 位作者 Chen Haidong Mou Junhui Kong Shengli 《International Journal of Mining Science and Technology》 SCIE EI 2013年第4期480-486,共7页
The technology of pressure relief gas drainage is one of the most effective and economic for preventing gas emissions in underground mines.Based on current understanding of strata breakage and fracture development in ... The technology of pressure relief gas drainage is one of the most effective and economic for preventing gas emissions in underground mines.Based on current understanding of strata breakage and fracture development in overlying strata,the current study divides the overlying strata into the following three longitudinal zones in terms of the state of gas flow:a turbulent channel zone,a transitional circulation channel zone and a seepage channel zone.According to the key strata discrimination theory of controlling the overlying strata,the calculation method establishes that the step-type expansion of the mining gas channel corresponds to the advancing distance of working face,and this research also confrms the expanding rule that the mining gas channel in overlying strata follows the advancing distance of mining working face.Based on the geological conditions of Xinjing Coal Mine of Yangquan,this paper researches the expanding rule of mining gas channel as well as the control action of the channel acting on the pressure relief flow under the condition of the remote protective layer,and got the distance using inversion that the step-type expanding of mining gas channel is corresponding to the advancing distance of working face,which verifes the accuracy and feasibility of theoretical calculation method proposed in this study.The research provides the theoretical basis for choosing the technology of pressure relief gas drainage and designing the parameters of construction. 展开更多
关键词 Remote mining overlying strata Gas channel expansion Gas flow control action Key strata
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Modified Modeling of the Heart by Applying Nonlinear Oscillators and Designing Proper Control Signal
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作者 Siroos Nazari Aghileh Heydari Javad Khaligh 《Applied Mathematics》 2013年第7期972-978,共7页
Rhythmic phenomena are one of the most striking manifestations of dynamic behavior in biological systems. Understanding the mechanisms of biological rhythms, is crucial for understanding the dynamic of life. Each type... Rhythmic phenomena are one of the most striking manifestations of dynamic behavior in biological systems. Understanding the mechanisms of biological rhythms, is crucial for understanding the dynamic of life. Each type of dynamic behaviors may be related to the performance of both normal physiology and pathological. Conductive system of the heart can be stimulated to action as a network of elements and these elements show the oscillatory behavior then can be modeled as nonlinear oscillators. This paper provides the mathematical model of the heart rhythm by considering different states of Vanderpol nonlinear oscillators. Proposed oscillator model is designed in order to reproduce time series of action potential of natural pacemakers cardiac, such as SA or AV nodes. So model of heart is presented by a system of differential equations and to be considered chaotic or nonchaotic for different parameters of the model by using of the 0-1 test. Finally, the model is synchronized by applying an appropriate control signal, if it is needed. 展开更多
关键词 HEART Oscillators Vander POL EQUATIONS Biological Systems action Potential control SYNCHRONIZATION
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Optimal Filtering Correction forMarine Dynamical Positioning Control System
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作者 Evgeny Veremey Margarita Sotnikova 《Journal of Marine Science and Application》 CSCD 2016年第4期452-462,共11页
This paper focuses on the problem of control law optimization for marine vessels working in a dynamical positioning (DP) regime. The approach proposed here is based on the use of a special unified multipurpose contr... This paper focuses on the problem of control law optimization for marine vessels working in a dynamical positioning (DP) regime. The approach proposed here is based on the use of a special unified multipurpose control law structure constructed on the basis of nonlinear asymptotic observers, that allows the decoupling of a synthesis into simpler particular optimization problems. The primary reason for the observers is to restore deficient information concerning the unmeasured velocities of the vessel. Using a number of separate items in addition to the observers, it is possible to achieve desirable dynamical features of the closed loop connection. The most important feature is the so-called dynamical corrector, and this paper is therefore devoted to solving its optimal synthesis in marine vessels controlled by DP systems under the action of sea wave disturbances. The problem involves the need for minimal intensity of the control action determined by high frequency sea wave components. A specialized approach for designing the dynamical corrector is proposed and the applicability and effectiveness of the approach are illustrated using a practical example of underwater DP system synthesis. 展开更多
关键词 dynamical positioning control law OBSERVER stability filter external disturbances sea waves CORRECTOR integral action
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Optimal Control of Wind Turbines under Islanded Operation
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作者 Magdi S. Mahmoud Mojeed O. Oyedeji 《Intelligent Control and Automation》 2017年第1期1-14,共14页
In this paper, an optimal control scheme for wind turbine output torque and power regulation under the influence of wind disturbances is presented. The system considered is a dynamic mechanical-based model with pitch ... In this paper, an optimal control scheme for wind turbine output torque and power regulation under the influence of wind disturbances is presented. The system considered is a dynamic mechanical-based model with pitch and generator torque actuators for controlling the pitch and generator torque. The performance of linear matrix inequality (LMI) formalism of linear quadratic regulator (LQR);linear quadratic regulator with integral action (LQRI) and model predictive control (MPC) were compared in response to a step change in wind disturbance. It is shown by Matlab simulation that the LQRI outperformed both LQR and MPC controllers. 展开更多
关键词 Wind TURBINE LINEAR QUADRATIC REGULATOR LINEAR QUADRATIC REGULATOR with Integral action Model PREDICTIVE control Output TORQUE Power Regulation
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