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气象观测场在汽车试验场中的应用研究
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作者 陈海建 《时代汽车》 2024年第14期172-174,178,共4页
汽车试验场作为汽车开展道路测试的重要场所,用于验证汽车产品的品质以及可靠性。除了场地道路外,气象条件作为汽车道路测试的重要一环,在《GB/T12534-1990汽车道路试验方法通则》中也有明确要求,如:试验时应是无雨无雾天气,相对湿度小... 汽车试验场作为汽车开展道路测试的重要场所,用于验证汽车产品的品质以及可靠性。除了场地道路外,气象条件作为汽车道路测试的重要一环,在《GB/T12534-1990汽车道路试验方法通则》中也有明确要求,如:试验时应是无雨无雾天气,相对湿度小于95%,气温0-40℃,风速不大于3m/s。同时气象条件也作为试验场道路管控的重要依据,实时风速、雨量、能见度等信息为场地管理者发布限速、限行、封场等通知提供必要参考依据,直接影响道路测试安全管控的及时性。因此,文章从气象观测场的建设、气象服务、异常天气道路管控等方面开展气象观测场在汽车试验场中的应用研究。 展开更多
关键词 products. In addition to the SITE roads METEOROLOGICAL conditions are an important part of AUTOMOTIVE ROAD testing and there are also clear requirements in the GB/T12534-1990 General Rules for AUTOMOTIVE ROAD Test Methods. For example the test should be conducted in rain and fog free weather with a relative humidity of less than 95% a temperature of 0-40 and a wind SPEED of no more than 3m/s. At the same time METEOROLOGICAL conditions also serve as an important basis for ROAD control in the test site. Real time information such as wind SPEED rainfall and visibility provides necessary reference for SITE managers to issue notices on SPEED limits SITE closures and trac restrictions directly aecting the timeliness of ROAD testing safety control. Therefore this article conducts research on the application of METEOROLOGICAL observation SITES in AUTOMOTIVE testing SITES from the construction of METEOROLOGICAL observation SITES METEOROLOGICAL services and abnormal weather ROAD control.
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Advancement in Wide Area Monitoring Protection and Control Using PMU’s Model in MATLAB/SIMULINK
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作者 Waheed Ur Rahman Muhammad Ali +7 位作者 Amjad Ullah Hafeez Ur Rahman Majid Iqbal Haseeb Ahmad Adnan Zeb Zeeshan Ali M. Ahsan Shahzad Beenish Taj 《Smart Grid and Renewable Energy》 2012年第4期294-307,共14页
A big step forward to improve power system monitoring and performance, continued load growth without a corresponding increase in transmission resources has resulted in reduced operational margins for many power system... A big step forward to improve power system monitoring and performance, continued load growth without a corresponding increase in transmission resources has resulted in reduced operational margins for many power systems worldwide and has led to operation of power systems closer to their stability limits and to power exchange in new patterns. These issues, as well as the on-going worldwide trend towards deregulation of the entire industry on the one hand and the increased need for accurate and better network monitoring on the other hand, force power utilities exposed to this pressure to demand new solutions for wide area monitoring, protection and control. Wide-area monitoring, protection, and control require communicating the specific-node information to a remote station but all information should be time synchronized so that to neutralize the time difference between information. It gives a complete simultaneous snap shot of the power system. The conventional system is not able to satisfy the time-synchronized requirement of power system. Phasor Measurement Unit (PMU) is enabler of time-synchronized measurement, it communicate the synchronized local information to remote station. 展开更多
关键词 WIDE Area MONITORING Protection and control (WAMPAC) Phasor Measurement uNit (PMU) WIDE Area MONITORING (WAM) Global Positioning System (GPS) WIDE Area controlLER (WAC) Local Area controlLER (LAC) Phase Angle MONITORING (PAM) Automatic Generation control (AGC) Circuit Breaker (CB) Current TRANSFORMERS (CTs) Potential TRANSFORMERS (PTs)
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Semantic model and optimization of creative processes at mathematical knowledge formation
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作者 Victor Egorovitch Firstov 《Natural Science》 2010年第8期915-922,共8页
The aim of this work is mathematical education through the knowledge system and mathematical modeling. A net model of formation of mathematical knowledge as a deductive theory is suggested here. Within this model the ... The aim of this work is mathematical education through the knowledge system and mathematical modeling. A net model of formation of mathematical knowledge as a deductive theory is suggested here. Within this model the formation of deductive theory is represented as the development of a certain informational space, the elements of which are structured in the form of the orientated semantic net. This net is properly metrized and characterized by a certain system of coverings. It allows injecting net optimization parameters, regulating qualitative aspects of knowledge system under consideration. To regulate the creative processes of the formation and realization of mathematical know- edge, stochastic model of formation deductive theory is suggested here in the form of branching Markovian process, which is realized in the corresponding informational space as a semantic net. According to this stochastic model we can get correct foundation of criterion of optimization creative processes that leads to “great main points” strategy (GMP-strategy) in the process of realization of the effective control in the research work in the sphere of mathematics and its applications. 展开更多
关键词 The Cybernetic Conception Optimization of control Quantitative And Qualitative Information Measures Modelling Intellectual Systems Neural Network MATHEMATICAL Education The control of Pedagogical PROCESSES CREATIVE Pedagogics Cognitive And CREATIVE PROCESSES Informal Axiomatic Thery SEMANTIC NET NET Optimization Parameters The Topology of SEMANTIC NET Metrization The System of Coverings Stochastic Model of CREATIVE PROCESSES At The Formation of MATHEMATICAL Knowledge Branching Markovian Process Great Main Points Strategy (GMP-Strategy) of The CREATIVE PROCESSES control Interdisciplinary Learning: Colorimetric Barycenter
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Adaptable and Dynamic Access Control Decision-Enforcement Approach Based on Multilayer Hybrid Deep Learning Techniques in BYOD Environment
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作者 Aljuaid Turkea Ayedh M Ainuddin Wahid Abdul Wahab Mohd Yamani Idna Idris 《Computers, Materials & Continua》 SCIE EI 2024年第9期4663-4686,共24页
Organizations are adopting the Bring Your Own Device(BYOD)concept to enhance productivity and reduce expenses.However,this trend introduces security challenges,such as unauthorized access.Traditional access control sy... Organizations are adopting the Bring Your Own Device(BYOD)concept to enhance productivity and reduce expenses.However,this trend introduces security challenges,such as unauthorized access.Traditional access control systems,such as Attribute-Based Access Control(ABAC)and Role-Based Access Control(RBAC),are limited in their ability to enforce access decisions due to the variability and dynamism of attributes related to users and resources.This paper proposes a method for enforcing access decisions that is adaptable and dynamic,based on multilayer hybrid deep learning techniques,particularly the Tabular Deep Neural Network Tabular DNN method.This technique transforms all input attributes in an access request into a binary classification(allow or deny)using multiple layers,ensuring accurate and efficient access decision-making.The proposed solution was evaluated using the Kaggle Amazon access control policy dataset and demonstrated its effectiveness by achieving a 94%accuracy rate.Additionally,the proposed solution enhances the implementation of access decisions based on a variety of resource and user attributes while ensuring privacy through indirect communication with the Policy Administration Point(PAP).This solution significantly improves the flexibility of access control systems,making themmore dynamic and adaptable to the evolving needs ofmodern organizations.Furthermore,it offers a scalable approach to manage the complexities associated with the BYOD environment,providing a robust framework for secure and efficient access management. 展开更多
关键词 BYOD security access control access control decision-enforcement deep learning neural network techniques TabularDNN MULTILAYER dynamic adaptable FLEXIBILITY bottlenecks performance policy conflict
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Adaptive Fuzzy Sliding Mode Controller for Grid Interface Ocean Wave Energy Conversion
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作者 Adel A. A. Elgammal 《Journal of Intelligent Learning Systems and Applications》 2014年第2期53-69,共17页
This paper presents a closed-loop vector control structure based on adaptive Fuzzy Logic Sliding Mode Controller (FL-SMC) for a grid-connected Wave Energy Conversion System (WECS) driven Self-Excited Induction Generat... This paper presents a closed-loop vector control structure based on adaptive Fuzzy Logic Sliding Mode Controller (FL-SMC) for a grid-connected Wave Energy Conversion System (WECS) driven Self-Excited Induction Generator (SEIG). The aim of the developed control method is to automatically tune and optimize the scaling factors and the membership functions of the Fuzzy Logic Controllers (FLC) using Multi-Objective Genetic Algorithms (MOGA) and Multi-Objective Particle Swarm Optimization (MOPSO). Two Pulse Width Modulated voltage source PWM converters with a carrier-based Sinusoidal PWM modulation for both Generator- and Grid-side converters have been connected back to back between the generator terminals and utility grid via common DC link. The indirect vector control scheme is implemented to maintain balance between generated power and power supplied to the grid and maintain the terminal voltage of the generator and the DC bus voltage constant for variable rotor speed and load. Simulation study has been carried out using the MATLAB/Simulink environment to verify the robustness of the power electronics converters and the effectiveness of proposed control method under steady state and transient conditions and also machine parameters mismatches. The proposed control scheme has improved the voltage regulation and the transient performance of the wave energy scheme over a wide range of operating conditions. 展开更多
关键词 GRID integration Wave Energy Conversion Systems Self-Excited Induction Generator (SEIG) Vector control Genetic Algorithm (GA) Particle SWARM Optimization (PSO) SLIDING Mode control (SMC) Fuzzy Logic control (FLC) MEMBERSHIP Function Tuning
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Recent Progress in Reinforcement Learning and Adaptive Dynamic Programming for Advanced Control Applications 被引量:4
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作者 Ding Wang Ning Gao +2 位作者 Derong Liu Jinna Li Frank L.Lewis 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期18-36,共19页
Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and ... Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and its applications to various advanced control fields. First, the background of the development of ADP is described, emphasizing the significance of regulation and tracking control problems. Some effective offline and online algorithms for ADP/adaptive critic control are displayed, where the main results towards discrete-time systems and continuous-time systems are surveyed, respectively.Then, the research progress on adaptive critic control based on the event-triggered framework and under uncertain environment is discussed, respectively, where event-based design, robust stabilization, and game design are reviewed. Moreover, the extensions of ADP for addressing control problems under complex environment attract enormous attention. The ADP architecture is revisited under the perspective of data-driven and RL frameworks,showing how they promote ADP formulation significantly.Finally, several typical control applications with respect to RL and ADP are summarized, particularly in the fields of wastewater treatment processes and power systems, followed by some general prospects for future research. Overall, the comprehensive survey on ADP and RL for advanced control applications has d emonstrated its remarkable potential within the artificial intelligence era. In addition, it also plays a vital role in promoting environmental protection and industrial intelligence. 展开更多
关键词 Adaptive dynamic programming(ADP) advanced control complex environment data-driven control event-triggered design intelligent control neural networks nonlinear systems optimal control reinforcement learning(RL)
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Four Algorithms for Boundary Control with Breaking in Space and Time
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作者 Vladimir Arabadzhi 《Journal of Applied Mathematics and Physics》 2019年第11期2891-2901,共11页
Typically, active control systems either have a priori complete information about the boundary-value problem and damped waves before switching on, or get it during the measurement process or accumulate and update info... Typically, active control systems either have a priori complete information about the boundary-value problem and damped waves before switching on, or get it during the measurement process or accumulate and update information online (identification process in adaptive systems). In this case, the boundary problem is completely imprinted in the information arrays of the control system. However, very often complete information about a boundary-value problem is not available in principle or this info is changing in time faster than the process of its accumulation. The article considers examples of boundary control algorithms based almost without any information. The algorithms presented in the article cannot be obtained within the framework of the harmonic representation of the problem by complex amplitudes. And these algorithms carry out fast control in microstructured boundary problems. It is shown that in some cases it is possible to find simple solutions if we remove restrictions: 1) on the spatio-temporal resolution of controlling elements of a boundary-value problem;2) on the high-frequency radiation of the controlled boundary. 展开更多
关键词 INCIDENT Low FREQUENCY Wave High FREQUENCY Technological Radiation Fast control in Microstructured Boundary Problems Binary BREAKER Breaker-Inverter Length of Damping SPINNING Acoustic BLADES Gas Stream SEICHE Waves
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Balance control during gait initiation: State-of-the-art and research perspectives 被引量:2
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作者 Eric Yiou Teddy Caderby +2 位作者 Arnaud Delafontaine Paul Fourcade Jean-Louis Honeine 《World Journal of Orthopedics》 2017年第11期815-828,共14页
It is well known that balance control is affected by aging, neurological and orthopedic conditions. Poor balance control during gait and postural maintenance are associated with disability, falls and increased mortali... It is well known that balance control is affected by aging, neurological and orthopedic conditions. Poor balance control during gait and postural maintenance are associated with disability, falls and increased mortality. Gait initiation-the transient period between the quiet standing posture and steady state walking-is a functional task that is classically used in the literature to investigate how the central nervous system(CNS) controls balance during a whole-body movement involving change in the base of support dimensions and center of mass progression. Understanding how the CNS in able-bodied subjects exerts this control during such a challenging task is a prerequisite to identifying motor disorders in populations with specific impairments of the postural system. It may also provide clinicians with objective measures to assess the efficiency of rehabilitation programs and better target interventions according to individual impairments. The present review thus proposes a state-of-the-art analysis on:(1) the balance control mechanisms in play during gait initiation in able bodied subjects and in the case of some frail populations; and(2) the biomechanical parameters used in the literature to quantify dynamic stability during gait initiation. Balance control mechanisms reviewed in this article included anticipatory postural adjustments, stance leg stiffness, foot placement, lateral ankle strategy, swing foot strike pattern and vertical center of mass braking. Based on this review, the following viewpoints were put forward:(1) dynamic stability during gait initiation may share a principle of homeostatic regulation similar to most physiological variables, where separate mechanisms need to be coordinated to ensure stabilization of vital variables, and consequently; and(2) rehabilitation interventions which focus on separate or isolated components of posture, balance, or gait may limit the effectiveness of current clinical practices. 展开更多
关键词 Balance control Anticipatory POSTURAL ADJUSTMENTS Leg stiffness FOOT placement Lateral ANKLE strategy FOOT STRIKE pattern Vertical center of mass braking Dynamic stability Gait initiation Biomechanics
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A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury
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作者 Qi Liu Jianye Xie +5 位作者 Runxue Zhou Jin Deng Weihong Nie Shuwei Sun Haiping Wang Chunying Shi 《Neural Regeneration Research》 SCIE CAS 2025年第2期503-517,共15页
Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug deliv... Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury. 展开更多
关键词 angiogenesis biomaterial blood-brain barrier cerebral ischemia/reperfusion injury control release drug delivery inflammation QK peptides matrix metalloproteinase-2 NEUROPROTECTION self-assembling nanofiber hydrogel
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Theory of Electromagnetism and Gravity —Modeling Earth as a Rotating Solenoid Coil
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作者 Greg Poole 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第4期663-692,共30页
Presented in this manuscript are conventional electrical engineering tools to model the earth as a rotating electrical machine. Calculations using known parameters of the earth and measured field data has resulted in ... Presented in this manuscript are conventional electrical engineering tools to model the earth as a rotating electrical machine. Calculations using known parameters of the earth and measured field data has resulted in new understanding of the earth’s electrical system and gyroscopic rotation. The material makeup of the inner earth is better understood based on derived permeability and permittivity constants. The planet has been modeled as simple coils and then as a parallel impedance circuit which has led to fundamental insight into planetary speed control and RLC combination for Schumann Resonance of 7.83 Hz. Torque and Voltage Constants and the inverse Speed Constant are calculated using three methods and all compare favorably with Newton’s Gravitational Constant. A helical resonator is referenced and Schumann’s Resonant ideal frequency is calculated and compared with others idealism. A new theory of gravity based on particle velocity selector at the poles is postulated. Two equations are presented as the needed links between Faraday’s electromagnetism and Newtonian physics. Acceleration and Deceleration of earth is explained as a centripetal governor. A new equation for planetary attraction and the attraction of atomic matter is theorized. Rotation of the earth’s electrical coil is explained in terms of the Richardson effect. Electric power transfer from the sun to the planets is proposed via Flux Transfer Events. The impact of this evolving science of electromagnetic modeling of planets will be magnified as the theory is proven, and found to be useful for future generations of engineers and scientists who seek to discover our world and other planets. 展开更多
关键词 Ampere Biot-Savart CENTRIPETAL Acceleration CENTRIPETAL GOVERNOR Dynamo EARTH Einstein-de Haas Effect Electric Field Electromagnetism Flux Transfer Events GOVERNOR control GRAVITY Gravitational CONSTANT Helical Resonator Lenz Law Lorentz Lightning Magnetic Field Motor CONSTANT Parallel Impedance Planet SPEED control Schumann Resonance Richardson Effect Solenoid SPEED CONSTANT Solar Power System Torque CONSTANT Velocity Selector Voltage CONSTANT
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From Control Theory to Gravitational Waves
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作者 Jean-Francois Pommaret 《Advances in Pure Mathematics》 2024年第2期49-100,共52页
When D:ξ→η is a linear ordinary differential (OD) or partial differential (PD) operator, a “direct problem” is to find the generating compatibility conditions (CC) in the form of an operator D<sub>1:</su... When D:ξ→η is a linear ordinary differential (OD) or partial differential (PD) operator, a “direct problem” is to find the generating compatibility conditions (CC) in the form of an operator D<sub>1:</sub>η→ξ such that Dξ = η implies D<sub>1</sub>η = 0. When D is involutive, the procedure provides successive first-order involutive operators D<sub>1</sub>,...,D<sub>n </sub>when the ground manifold has dimension n. Conversely, when D<sub>1</sub> is given, a much more difficult “inverse problem” is to look for an operator D:ξ→η having the generating CC D<sub>1</sub>η = 0. If this is possible, that is when the differential module defined by D<sub>1</sub> is “torsion-free”, that is when there does not exist any observable quantity which is a sum of derivatives of η that could be a solution of an autonomous OD or PD equation for itself, one shall say that the operator D<sub>1</sub> is parametrized by D. The parametrization is said to be “minimum” if the differential module defined by D does not contain a free differential submodule. The systematic use of the adjoint of a differential operator provides a constructive test with five steps using double differential duality. We prove and illustrate through many explicit examples the fact that a control system is controllable if and only if it can be parametrized. Accordingly, the controllability of any OD or PD control system is a “built in” property not depending on the choice of the input and output variables among the system variables. In the OD case and when D<sub>1</sub> is formally surjective, controllability just amounts to the formal injectivity of ad(D<sub>1</sub>), even in the variable coefficients case, a result still not acknowledged by the control community. Among other applications, the parametrization of the Cauchy stress operator in arbitrary dimension n has attracted many famous scientists (G. B. Airy in 1863 for n = 2, J. C. Maxwell in 1870, E. Beltrami in 1892 for n = 3, and A. Einstein in 1915 for n = 4). We prove that all these works are already explicitly using the self-adjoint Einstein operator, which cannot be parametrized and the comparison needs no comment. As a byproduct, they are all based on a confusion between the so-called div operator D<sub>2</sub> induced from the Bianchi operator and the Cauchy operator, adjoint of the Killing operator D which is parametrizing the Riemann operator D<sub>1</sub> for an arbitrary n. This purely mathematical result deeply questions the origin and existence of gravitational waves, both with the mathematical foundations of general relativity. As a matter of fact, this new framework provides a totally open domain of applications for computer algebra as the quoted test can be studied by means of Pommaret bases and related recent packages. 展开更多
关键词 Differential Operator Differential Sequence Killing Operator Riemann Operator Bianchi Operator Cauchy Operator control Theory controllability Elasticity General Relativity
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Analysis of debris flow control effect and hazard assessment in Xinqiao Gully,Wenchuan M_(s)8.0 earthquake area based on numerical simulation 被引量:1
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作者 Chang Yang Yong-bo Tie +3 位作者 Xian-zheng Zhang Yan-feng Zhang Zhi-jie Ning Zong-liang Li 《China Geology》 CAS CSCD 2024年第2期248-263,共16页
Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the eff... Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the effectiveness of the debris flow control project and evaluated the debris flow hazards.Through field investigation and numerical simulation methods,the indicators of flow intensity reduction rate and storage capacity fullness were proposed to quantify the effectiveness of the engineering measures in the debris flow event.The simulation results show that the debris flow control project reduced the flow intensity by41.05%to 64.61%.The storage capacity of the dam decreases gradually from upstream to the mouth of the gully,thus effectively intercepting and controlling the debris flow.By evaluating the debris flow of different recurrence intervals,further measures are recommended for managing debris flow events. 展开更多
关键词 Landslide Debris flow Hazard assessment Numerical simulation OpenLISEM Prevention and control project Wenchuan M_(s)8.0 earthquake Xinqiao Gully Sichuan province Geological hazards survey engineering
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Treatment of Atherosclerotic Disease of the Femoral Artery: Randomized Controlled Trials and Meta-Analyses. Should You Be Sceptical?
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作者 Raymond Englund 《Surgical Science》 2019年第7期235-254,共20页
A narrative review of the data provided by Randomised Controlled clinical trials and meta-analyses was undertaken to assess how much reliance a clinician could place on these in selecting a treatment for patients with... A narrative review of the data provided by Randomised Controlled clinical trials and meta-analyses was undertaken to assess how much reliance a clinician could place on these in selecting a treatment for patients with disease of the Femoral artery. An attempt was made to detect and review every clinical trial and meta-analysis published on treatments relating to disease of the femoral artery but not relating to drug treatment. Disease of the femoral artery in >65 years age group occurs in approximately 20% of the population but symptomatology was present in 40%. In almost all trials the predominant (>90%) indication for treatment was intermittent claudication. In this setting, clinical benefit was limited and did not extend beyond 12 months. Mortality, from co-morbidities was high. The Basil Trial was the only one to examine intervention for critical limb ischemia. The results for Bypass surgery and Percutaneous transarterial balloon angioplasty (PTA) were equivalent. There is little evidence to support the use of PTA or stenting other than in the treatment of patients with critical limb ischemia. 展开更多
关键词 Femoral Artery Stent (Nitinol DRUG-ELUTING Covered) Percutaneous Balloon Angioplasty Drug Eluting BALLOONS RANDOMISED controlled Trials META-ANALYSES Intermittent CLAUDICATION Critical Limb Ischemia PATENCY Clinical Benefit
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Glucagon-like peptide-1 receptor agonists:Exploring the mechanisms from glycemic control to treatment of multisystemic diseases
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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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Robust <i>H</i><sub>∞</sub>Observer-Based Tracking Control for the Photovoltaic Pumping System
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作者 Iliass Ouachani Abdelhamid Rabhi +2 位作者 Ahmed El Hajjaji Belkassem Tidhaf Smail Zouggar 《Energy and Power Engineering》 2014年第9期266-277,共12页
In this paper, we propose a H∞ robust observer-based control DC motor based on a photovoltaic pumping system. Maximum power point tracking is achieved via an algorithm using Perturb and Observe method, with array vol... In this paper, we propose a H∞ robust observer-based control DC motor based on a photovoltaic pumping system. Maximum power point tracking is achieved via an algorithm using Perturb and Observe method, with array voltage and current being used to generate the reference voltage which should be the PV panel’s operating voltage to get maximum available power. A Takagi-Sugeno (T-S) observer has been proposed and designed with non-measurable premise variables and the conditions of stability are given in terms of Linear Matrix Inequality (LMI). The simulation results show the effectiveness and robustness of the proposed method. 展开更多
关键词 PHOTOVOLTAIC Pumping System FUZZY controller H Takagi-Sugino (TS) FUZZY Model OBSERVER Stability Linear Matrix Inequalities (LMIs) Maximum Power Point Tracking (MPPT) Unmeasurable Premise Variables
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Medical errors, infection-control breaches and the use of adulterated and misbranded medical devices 被引量:3
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作者 Lawrence F Muscarella 《World Journal of Clinical Infectious Diseases》 2012年第2期13-27,共15页
Several well-publicized cases of improper cleaning,disinfection or sterilization of contaminated reusable medical equipment that posed an increased risk of patientto-patient disease transmission were reported within t... Several well-publicized cases of improper cleaning,disinfection or sterilization of contaminated reusable medical equipment that posed an increased risk of patientto-patient disease transmission were reported within the past few years,resulting in the notification of approximately 20 000 patients.These medical errors,the specific infection-control standards they breached,and assessments of the risk of infection associated with each are discussed.Other topics discussed include the Food and Drug Administration’s(FDA)regulation of medical devices and infection-control products;the use of adulterated,misbranded,and investigational devices;consent decrees and associated Certificates of Medical Necessity;and informed patient consent.Focus is placed on liquid chemical sterilization,its history,and the FDA’s recent censure and discontinuation of a medical device labeled with this claim,namely,the STERIS System 1 processor.Recommendations are provided for healthcare facilities,regulatory agencies,manufacturers of reusable medical devices,and professional healthcare organizations and administrations to improve public health and prevent healthcareassociated infections. 展开更多
关键词 INFECTION control STERILIZATION Disinfection DISEASE NOTIFICATION Infectious DISEASE transmission Communicable DISEASE control Decontamination Medical errors Government regulation Equipment and supplies hospital ASEPTIC technique Liquid chemical STERILIZATION
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Boundary Control Problem of Infinite Order Distributed Hyperbolic Systems Involving Time Lags 被引量:2
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作者 Bahaa Gaber Mohamed 《Intelligent Control and Automation》 2012年第3期211-221,共11页
Various optimal boundary control problems for linear infinite order distributed hyperbolic systems involving constant time lags are considered. Constraints on controls are imposed. Necessary and sufficient optimality ... Various optimal boundary control problems for linear infinite order distributed hyperbolic systems involving constant time lags are considered. Constraints on controls are imposed. Necessary and sufficient optimality conditions for the Neumann problem with the quadratic performance functional are derived. 展开更多
关键词 BOUNDARY control (n × n) Hyperbolic Systems Time Lags DISTRIBUTED control Problems NEUMANN Conditions Existence and UNIQUENESS of Solutions Infinite Order Operator
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Social Cost Analysis of Biological Control Technology for Crop Diseases and Insect Pests
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作者 Jie XIE Lingling XIAO +4 位作者 Jinyu ZHAO Shoumei WAN Jian TANG Xiaolei JI Jing PENG 《Asian Agricultural Research》 2024年第8期14-16,共3页
With the rapid development of modern agriculture,the prevention and control of crop diseases and insect pests has become an important part to ensure the safety of agricultural production,the quality of agricultural pr... With the rapid development of modern agriculture,the prevention and control of crop diseases and insect pests has become an important part to ensure the safety of agricultural production,the quality of agricultural products and the safety of agricultural ecological environment.Although the effect of traditional chemical prevention and control technology is remarkable,the health risks and environmental problems brought by it should not be ignored.As a green and environmentally friendly means of prevention and control,biological prevention and control technology has gradually become a hot research topic and a trend of agricultural production.This paper is intended to comprehensively evaluate the social costs of biological control technologies for crop diseases and pests,including the health risks reduced,environmental improvements,economic benefits,and barriers to promotion,and put forward corresponding policy recommendations. 展开更多
关键词 CROPS DISEASES and INSECT PESTS BIOLOGICAL control SOCIAL cost
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Active Disturbance Rejection Control for a Multiple-Flexible-Link Manipulator 被引量:1
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作者 Yanfang Liu Hong Liu Yao Meng 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2018年第1期18-28,共11页
The control problem of multiple-flexible-link manipulators( MFLMs) is studied in this paper.The dynamic model of MFLM is derived and separated into two-time scale by utilizing the singular perturbation technique. The ... The control problem of multiple-flexible-link manipulators( MFLMs) is studied in this paper.The dynamic model of MFLM is derived and separated into two-time scale by utilizing the singular perturbation technique. The active disturbance rejection control( ADRC) is adopted to the slow subsystem to track a desired trajectory. The proposed ADRC structure preshapes the desired trajectory by utilizing the tracking differentiator,estimates the disturbance and internal states with an extended state observer,and guarantees a robust performance by combining a feedback controller with a feedforward term. Two types of feedback controllers are designed,proportional derivative( PD) controller and nonlinear PD( NPD) controller. For the fast subsystem,a fast stabilizing control is designed according to the standard linear quadratic regulator approach. Simulations are performed to evaluate the proposed control scheme.Results show that,compared with the traditional PD controller,the ADRC structure based control scheme has smaller overshot and shorter settling time,suppresses vibration quickly,and is robust to the maneuver speed. In general,the control scheme utilizing ADRC structure and NPD feedback controller shows better performance. 展开更多
关键词 multiple-flexible-link manipulator ( MFLM) active disturbance REJECTION control (ADRC) nonlinear proportional plus derivative ( NPD) tracking DIFFERENTIATOR ( TD) extended state observer ( ESO)
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A Novel Cascaded PID Controller for Automatic Generation Control Analysis With Renewable Sources 被引量:5
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作者 Aurobindo Behera Tapas Kumar Panigrahi +1 位作者 PrakashK·Ray Arun Kumar Sahoo 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第6期1438-1451,共14页
Present day power scenarios demand a high quality uninterrupted power supply and needs environmental issues to be addressed. Both concerns can be dealt with by the introduction of the renewable sources to the existing... Present day power scenarios demand a high quality uninterrupted power supply and needs environmental issues to be addressed. Both concerns can be dealt with by the introduction of the renewable sources to the existing power system. Thus, automatic generation control(AGC) with diverse renewable sources and a modified-cascaded controller are presented in the paper.Also, a new hybrid scheme of the improved teaching learning based optimization-differential evolution(hITLBO-DE) algorithm is applied for providing optimization of controller parameters. A study of the system with a technique such as TLBO applied to a proportional integral derivative(PID), integral double derivative(IDD) and PIDD is compared to hITLBO-DE tuned cascaded controller with dynamic load change.The suggested methodology has been extensively applied to a 2-area system with a diverse source power system with various operation time non-linearities such as dead-band of, generation rate constraint and reheat thermal units. The multi-area system with reheat thermal plants, hydel plants and a unit of a wind-diesel combination is tested with the cascaded controller scheme with a different controller setting for each area. The variation of the load is taken within 1% to 5% of the connected load and robustness analysis is shown by modifying essential factors simultaneously by± 30%. Finally, the proposed scheme of controller and optimization technique is also tested with a 5-equal area thermal system with non-linearities. The simulation results demonstrate the superiority of the proposed controller and algorithm under a dynamically changing load. 展开更多
关键词 Automatic generation control(AGC) cascaded controlLER hybrid improved teaching learning based optimization-differential evolution(hITLBO-DE) algorithm INTEGRAL of SQUARE time multiplied by SQUARE error(ISTSE)
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