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Robust State Feedback H_∞Control for Dynamic Biped Robot Based on T-S Fuzzy Model
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作者 HUAI Chuangfeng FANG Yuefa (Department of Mechanical Engineering,Beijing Jiaotong University,Beijing 10044,E-mall: hcf811225@163.com) 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S3期951-955,共5页
T-S fuzzy model was applied to describe nonlinear system and global fuzzy model was expressed by the form of uncertain system.Based on robust state feedback H_∞control strategy,designed a global asymptotic steady fuz... T-S fuzzy model was applied to describe nonlinear system and global fuzzy model was expressed by the form of uncertain system.Based on robust state feedback H_∞control strategy,designed a global asymptotic steady fuzzy model.This control system can use the experimental input-output data pairs for the biped robot learning and walking with dynamic balance.It is proved by simulation result that robust state feedback H_∞control method based on T-S fuzzy model can effectively restrain the effect of model uncertainties and external disturbance acting on biped robot.From these works,we showed the satisfactory performance of joint tracking without any chattering. 展开更多
关键词 ROBUST H_∞control state feedback T-S FUZZY model BIPED walking robot FUZZY system
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Delay-dependent robust H_∞control of convex polyhedral uncertain fuzzy systems 被引量:1
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作者 Gong Cheng Su Baoku 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第6期1191-1198,共8页
The robust H∞ control problem for a class of uncertain Takagi-Sugeno fuzzy systems with timevarying state delays is studied. The uncertain parameters are supposed to reside in a polytope. Based on the delay-dependent... The robust H∞ control problem for a class of uncertain Takagi-Sugeno fuzzy systems with timevarying state delays is studied. The uncertain parameters are supposed to reside in a polytope. Based on the delay-dependent Lyapunov functional method, a new delay-dependent robust H∞ fuzzy controller, which depends on the size of the delays and the derivative of the delays, is presented in term of linear matrix inequalities (LMIs). For all admissible uncertainties and delays, the controller guarantees not only the asymptotic stability of the system but also the prescribed H∞ attenuation level. In addition, the effectiveness of the proposed design method is demonstrated by a numerical example. 展开更多
关键词 robust H∞ control DELAY-DEPENDENT polyhedral uncertainty fuzzy systems
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Finite Frequency Fuzzy H∞Control for Uncertain Active Suspension Systems With Sensor Failure 被引量:5
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作者 Zhenxing Zhang Hongyi Li +1 位作者 Chengwei Wu Qi Zhou 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2018年第4期777-786,共10页
This paper investigates the problem of finite frequency fuzzy H_∞ control for uncertain active vehicle suspension systems, in which sensor failure is taken into account. TakagiSugeno(T-S) fuzzy model is established f... This paper investigates the problem of finite frequency fuzzy H_∞ control for uncertain active vehicle suspension systems, in which sensor failure is taken into account. TakagiSugeno(T-S) fuzzy model is established for considered suspension systems. In order to describe the sensor fault effectively, a corresponding model is introduced. A vital performance index,H_∞ performance, is utilized to measure the drive comfort. In the framework of Kalman-Yakubovich-Popov theory, the H_∞ norm from external perturbation to controlled output is optimized effectively in the frequency domain of 4 Hz-8 Hz to enhance ride comfort level. Meanwhile, three suspension constrained requirements, i.e., ride comfort level, manipulation stability,suspension deflection are also guaranteed. Furthermore, sufficient conditions are developed to design a fuzzy controller to guarantee the desired performance of active suspension systems. Finally, the proposed control scheme is applied to a quarter-vehicle active suspension, and simulation results are given to illustrate the effectiveness of the proposed approach. 展开更多
关键词 Active vehicle suspension systems finite frequency control sensor failure Takagi-Sugeno fuzzy model
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Interpolated Bumpless Transfer Control for Asynchronously Switched Linear Systems
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作者 Shengao Lu Tong Wu +2 位作者 Lixian Zhang Jianan Yang Ye Liang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第7期1579-1590,共12页
This paper revisits the problem of bumpless transfer control(BTC) for discrete-time nondeterministic switched linear systems. The general case of asynchronous switching is considered for the first time in the field of... This paper revisits the problem of bumpless transfer control(BTC) for discrete-time nondeterministic switched linear systems. The general case of asynchronous switching is considered for the first time in the field of BTC for switched systems. A new approach called interpolated bumpless transfer control(IBTC) is proposed, where the bumpless transfer controllers are formulated with the combination of the two adjacent modedependent controller gains, and are interpolated for finite steps once the switching is detected. In contrast with the existing approaches, IBTC does not necessarily run through the full interval of subsystems, as well as possesses the time-varying controller gains(with more flexibility and less conservatism) achieved from a control synthesis allowing for the stability and other performance of the whole switched system. Sufficient conditions ensuring stability and H_(∞) performance of the underlying system by IBTC are developed, and numerical examples verify the theoretical findings. 展开更多
关键词 Asynchronous switching bumpless transfer H_∞control switched systems
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基于ControlVAE的约束嵌入稠密时变阵列构建
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作者 孙文力 原达 姜新波 《电子学报》 EI CAS CSCD 北大核心 2024年第1期354-363,共10页
在对探地雷达(Ground Penetrating Radar,GPR)数据进行三维建模与可视化分析过程中,其所依赖的三维时变阵列通常是由一维数据道或二维阵列间接生成的.由于采集到的数据往往比较稀疏,且存在不规则偏移,需要进行稠密处理,以获得高密度三... 在对探地雷达(Ground Penetrating Radar,GPR)数据进行三维建模与可视化分析过程中,其所依赖的三维时变阵列通常是由一维数据道或二维阵列间接生成的.由于采集到的数据往往比较稀疏,且存在不规则偏移,需要进行稠密处理,以获得高密度三维时变阵列.本文提出了一种基于可控变分自编码(Controllable Variational AutoEncoder,ControlVAE)的约束嵌入稠密时变阵列构建方法 .使用基于ControlVAE的时变数据重构网络,通过隐空间采样插值和深浅层特征信息的融合,生成接近真实分布的伪道数据来增加阵列密度.构建了基于尺度不变特征变换的数据配准模块,提取道间梯度特征与结构对称性特征,可以在时空域内完成数据配准.同时将浅层特征作为约束信息嵌入数据重构网络,以消除数据道偏移对阵列生成的影响.实验结果表明,本文方法仅使用单测线二维B-scan数据集即可重建稠密时变阵列,可以有效降低重构模型累积误差,提高面对复杂真实数据时的鲁棒性. 展开更多
关键词 时变阵列 数据生成 探地雷达 约束嵌入 可控变分自编码模型
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Blood Pressure Profile and Glycemic Control of Type 2 Diabetics and Hypertensives at the Yalgado Ouedraogo University Hospital: A Review of 116 Cases
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作者 G. R. C. Millogo A. Thiam +6 位作者 Y. Kambiré E. Nongkouni S. E. Dabiré L. J. Kagambéga J. K. Kologo V. N. Yaméogo P. Zabsonré 《World Journal of Cardiovascular Diseases》 CAS 2024年第1期61-76,共16页
Objective: The association hypertension and diabetes is important. The two pathologies may influence each other. The aim was to study the correlation between glycemic control and blood pressure control and to determin... Objective: The association hypertension and diabetes is important. The two pathologies may influence each other. The aim was to study the correlation between glycemic control and blood pressure control and to determine the factors associated with blood pressure control. Methodology: This was a descriptive cross-sectional study with an analytical focus over 7 months. Patients were recruited as outpatients and all underwent ambulatory blood pressure measure, glycated hemoglobin and creatinine measurements, and assessment of compliance with treatment. Results: During this period 116 patients were collected. The predominance was female 69%. The mean age of the patients was 62 ± 7 years with a peak between 60 and 70 years. The average age of hypertension was 12 years and that of diabetes 6 1/2 years. The most frequently associated cardiovascular risk factor was a sedentary lifestyle (71.5%) after age. 57.8% of patients were not controlled at the office, with a predominance of systolic hypertension (58.2%). 61.6% of patients were controlled by ambulatory blood pressure measure, a rate of 47.8% of white coat hypertension. Glycemic control was observed in 42.2% of cases and 87% of patients had good renal function (glomerular filter rate ≥ 60 ml/mn). Therapeutic compliance was good in 53.4% of cases and dual therapy was the most used therapeutic modality 44.8% (52 patients) followed by triple therapy. The factors associated with poor blood pressure control were glycemic imbalance, non-compliance and monotherapy. Dual therapy had a protective effect. Conclusion: The association of hypertension and type 2 diabetes is frequent. The risk of occurrence increases with age. Ambulatory blood pressure measure is the best method to assess blood pressure control. Optimization of blood pressure control should also include optimization of glycemic control. 展开更多
关键词 Blood Pressure control Glycemic control Hypertensive and Diabetic Patients
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Unified Control Theory from PID to ACPID
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作者 Zhezhao Zeng Yuqi Tang 《Advances in Pure Mathematics》 2024年第7期523-545,共23页
To address the challenge of achieving unified control across diverse nonlinear systems, a comprehensive control theory spanning from PID (Proportional-Integral-Derivative) to ACPID (Auto-Coupling PID) has been propose... To address the challenge of achieving unified control across diverse nonlinear systems, a comprehensive control theory spanning from PID (Proportional-Integral-Derivative) to ACPID (Auto-Coupling PID) has been proposed. The primary concept is to unify all intricate factors, including internal dynamics and external bounded disturbance, into a single total disturbance. This enables the mapping of various nonlinear systems onto a linear disturbance system. Based on the theory of PID control and the characteristic equation of a critically damping system, Zeng’s stabilization rules (ZSR) and an ACPID control force based on a single speed factor have been designed. ACPID control theory is both simple and practical, with significant scientific significance and application value in the field of control engineering. 展开更多
关键词 Insert Nonlinear Systems PID control ACPID control Total Disturbance Unified control Theory Zeng’s Stabilization Rules (ZSR)
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Associated Factors to Poor Blood Pressure Control in Hypertensives Followed Up at the Campus University Hospital of Lome (Togo)
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作者 Soulemane Pessinaba Yaovi Mignazonzon Afassinou +9 位作者 Wiyao Dieudonné Kaziga Komlavi Yayehd Kolani Lamboni Sélim Bolarinwa Mohamed Kpélafia Ekpe Togbossi Akpe Adzodo Machihude Pio Soodougoua Baragou Findibé Damorou 《World Journal of Cardiovascular Diseases》 CAS 2024年第6期374-380,共7页
Introduction: Hypertension is a real public health issue and its control is very difficult. We aim to determine the frequency of uncontrolled hypertension in hypertensive patients followed up as an outpatient at the c... Introduction: Hypertension is a real public health issue and its control is very difficult. We aim to determine the frequency of uncontrolled hypertension in hypertensive patients followed up as an outpatient at the campus university hospital of Lome (Togo) and to search for the associated factors. Methodology: The study was cross-sectional, descriptive and analytical, carried out from February (2022) to August 2022 in 260 hypertensive patients aged 22 years old, followed up (on an) as an outpatient for at least 3 months at the Lome University Hospital campus. A univariate then multivariate analysis were conducted in order to highlight the most common factors significantly linked to uncontrolled. Results: The mean age of hypertensives was 56.4 ± 12.7 years, the sex ratio (M/F) was 0.59. Prevalence of uncontrolled blood pressure was 42%. Associated Factors to poor blood pressure control in our study were age > 60 years (OR = 1.6 CI [1.17 - 2.50]), low socio-economic level (OR = 2.2 CI [1.96 - 4.33]), high cardiovascular risk level (OR = 3.1 CI [2.18 - 4.52]), non-adherence to regular blood pressure monitoring (OR = 3.3 CI [2.21 - 5.55]), low compliance to treatment (OR = 4.1 CI [2.33 - 6.76]) and a chronic renal failure (OR = 2.1 CI [1.21 - 3.10]). Conclusion: Nearly half of the hypertensives in our study had poorly controlled blood pressure by antihypertensive treatment medication. The factors of this poor control were age > 60 years, low socio-economic level, high or very high level of cardiovascular risk, low compliance to treatment, and renal failure. 展开更多
关键词 HYPERTENSION Poor control Associated factors TOGO
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Screening, Treatment and Control of High Blood Pressure on Five Sites in Mali
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作者 Mamadou Touré Sagara Ibrahima +19 位作者 Youssouf Camara Hamidou Oumar Bâ Ibrahima Sangaré Djénébou Traoré Noumou Sidibé Fousseyni Samassékou Massama Konaté Coumba Thiam Doumbia Asmaou Maiga Réné-Marie Dakouo Hamidou Camara Sako Mariam Sidibé Samba Adama Sogodogo Boubacar Diarra Boubacar Sonfo Aladji Traoré Mamadou Diakité Ilo Bella Diall Ichaka Menta 《World Journal of Cardiovascular Diseases》 CAS 2024年第5期322-332,共11页
Introduction: High blood pressure is defined as blood pressure greater than or equal to 140 mm Hg for systolic and or 90 mm Hg for diastolic. It constitutes a major public health problem, the leading chronic disease i... Introduction: High blood pressure is defined as blood pressure greater than or equal to 140 mm Hg for systolic and or 90 mm Hg for diastolic. It constitutes a major public health problem, the leading chronic disease in the world. The objective was to determine the prevalence, treatment rate and control of hypertension. Methods: This was a cross-sectional and descriptive study which took place over a period of 6 months in a hospital environment and in the general population. Results: Of the 1000 participants, 637 had hypertension, giving a prevalence of 63.70% with a female predominance. Thirty-three percent (33%) were unaware of their high blood pressure. The age group 60 and more was the most represented (44%). A proportion of 33 and 23.20 were overweight and obese participants, respectively. Male subjects were more overweight than female, unlike obesity which was more common among female subjects. Sixty-two percent (62%) of hypertensives were treated, of whom 44% were non-compliant. The excessively high cost and consumption of medications as needed were the main factors in therapeutic non-compliance. Twenty-two percent (22%) of all hypertensive patients and 35% of treated hypertensive patients were controlled. Women were more treated but less observant and less controlled than men. Therapeutic coverage and combination therapy rates were lower in rural areas. Hypertensives who had a high level of education were better treated and controlled than those who had no level. Conclusion: High blood pressure remains a real public health problem in Mali. It is more common in people aged 60 and over and in females. One in three hypertensives were unaware of their hypertension. The majority received antihypertensive treatments, but only a minority of them had their hypertension controlled. 展开更多
关键词 High Blood Pressure SCREENING control Rate MALI
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Matrix Riccati Equations in Optimal Control
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作者 Malick Ndiaye 《Applied Mathematics》 2024年第3期199-213,共15页
In this paper, the matrix Riccati equation is considered. There is no general way for solving the matrix Riccati equation despite the many fields to which it applies. While scalar Riccati equation has been studied tho... In this paper, the matrix Riccati equation is considered. There is no general way for solving the matrix Riccati equation despite the many fields to which it applies. While scalar Riccati equation has been studied thoroughly, matrix Riccati equation of which scalar Riccati equations is a particular case, is much less investigated. This article proposes a change of variable that allows to find explicit solution of the Matrix Riccati equation. We then apply this solution to Optimal Control. 展开更多
关键词 Optimal control Matrix Riccati Equation Change of Variable
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Secondary Metabolites of Entomopathogenic Fungi, Biological Alternative for the Control of Agricultural Pests and Disease: Present and Perspectives
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作者 Nallely San Juan-Maldonado Silvia Rodríguez-Navarro +2 位作者 Alejandro Angel-Cuapio José Norberto Vásquez Bonilla Juan Esteban Barranco-Florido 《Advances in Enzyme Research》 CAS 2024年第1期1-15,共15页
The use of entomopathogenic fungi (EF) in recent years has been highly effective against the different orders of insects considered pests of agricultural importance and their conidia have been commonly applied, but it... The use of entomopathogenic fungi (EF) in recent years has been highly effective against the different orders of insects considered pests of agricultural importance and their conidia have been commonly applied, but it has been reported that these are sensitive to the environmental conditions. For this reason, biopesticides products have been formulated based on secondary metabolites, recently. These biomolecules participate as biological control agent, such as: cyclic depsipeptides, amino acids, polyketides, polyphenols and terpenoids, affecting their morphology, life cycle and insect behavior. The use of secondary metabolites of entomopathogenic fungi opens the possibility of application in a more efficient way for the control of agricultural pests in a compatible with the environment and human health;therefore, it is important to know, analyzing the type of molecules, their effects, and their different methods of application. 展开更多
关键词 Secondary Metabolites Entomopathogenic Fungi Biological control Agent
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Study of the Constraints of Millet Production (Pennisetum glaucum (L.) R. Br.) and the Peasant Perception of Biological Control in the Tahoua Region
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作者 Rabé Mahamane Moctar Hama Oumarou +3 位作者 Issaka Rabo Salissou Abdoulaye Amoustapha Soumaila Bakoye Nouhou Ousmane Baoua Ibrahim 《Agricultural Sciences》 2024年第1期1-14,共14页
Millet (Pennisetum glaucum (L.) R. Br.) is the Sahelian crop par excellence due to its adaptation to the particular production conditions in this region. Unfortunately, in recent years this crop has been threatened by... Millet (Pennisetum glaucum (L.) R. Br.) is the Sahelian crop par excellence due to its adaptation to the particular production conditions in this region. Unfortunately, in recent years this crop has been threatened by very strong parasitic pressure and drought during the production period. The objective of this study is to analyze the main constraints of millet production and the solutions known to producers. A survey was carried out in November 2022 with a sample of 298 producers in five municipalities in the Tahoua region. The main constraints are drought and pressure from crop pests (locust, millet ear miner, floricultural insects) according to 57.9% of respondents. The millet ear miner is the most formidable pest according to 55% of respondents. Thus, the average yield obtained in a year of good production without the leafminer is 194 kg/ha and that obtained in a year of millet ear leafminer is around 27 kg to 43 kg/ha depending on the municipality. The yield obtained this last campaign after the attack of this leafminer varies from 64 to 77 kg/ha depending on the municipalities compared to a potential yield of over 1000 kg/ha. More than half of producers (58.1%) are unaware of the existence of biological control compared to only 12.5% who are aware of this alternative method. Work to popularize this technology is necessary in the five municipalities and the entire region in general. 展开更多
关键词 Biological control Ear Miner MILLET
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Remote Control of Bovine Catalase Activity with Specific Frequencies of Human and Bovine Catalase with and without Bound NADP+
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作者 Thibaud Etienne d’Oultremont 《Advances in Enzyme Research》 CAS 2024年第2期17-34,共18页
Remote control enzyme technology is widely used today through resonance. In this study, we showed that the use of frequencies of the catalase enzyme itself to increase enzymatic rate is successful not only in test tub... Remote control enzyme technology is widely used today through resonance. In this study, we showed that the use of frequencies of the catalase enzyme itself to increase enzymatic rate is successful not only in test tubes but also remotely. The present study also suggests that, under optimal temperature, the use of bovine catalase frequency (the specific frequency of that enzyme) has a superior rate promoting vibration than the human catalase frequency, and so increases very significantly the chemical rate of bovine catalase (about 120% at 40˚C). It also suggests that bovine catalase subjected to bovine and human frequencies with catalase bound NADP+ experienced more resonance weight towards NADP+ and so were more slowly reduced back to catalase bound NADPH, increasing compound II formation rate, and slowing down the catalase activity rate. 展开更多
关键词 Remote control CATALASE Frequency Rate Promoting Vibration (RPV) NADP
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Practice of Infection Prevention and Control Strategies in Risk Departments during the COVID-19 Epidemic
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作者 Minfang Wang Wenyi Ye +7 位作者 Jiefeng Huang Yuexian Zhu Xuxia Yu Hao Huang Fang Xu Bo Jin Ying Yang Tieer Gan 《Advances in Infectious Diseases》 CAS 2024年第1期1-12,共12页
Objective: To explore the practice and application of infection prevention and control strategies in risk departments during the COVID-19 epidemic, and to formulate the infection prevention and control measures to pro... Objective: To explore the practice and application of infection prevention and control strategies in risk departments during the COVID-19 epidemic, and to formulate the infection prevention and control measures to provide advice and guidance in risk departments. Methods: According to the latest plan of diagnosis and treatment, prevention and control issued by the National Health Commission, expert advice and consensus, combined with the actual situation in our hospital, a series of infection prevention and control measures of COVID-19 in risk department was formulated. Results: During the epidemic period, the prevention and control measures of nine risk departments including emergency operation, anesthesiology, endoscopy center, blood purification center, otolaryngology, stomatology, medical imaging department, medical cosmetology department and pulmonary function room were established from six aspects, including pre-examination and screening, medical technology control, personnel management, personal protection, environmental disinfection, medical waste disposal, etc. Conclusion: During the epidemic period, the infection prevention and control strategy of risk departments is one of the key links to control the spread of the epidemic, and risk departments must pay attention to and strictly implement various infection prevention and control measures. 展开更多
关键词 COVID-19 Risk Department Infection Prevention and control STRATEGY PRACTICE
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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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Structural Controls Analysis and Its Correlation with Geothermal Occurrence at Barrier Volcanic Complex (BVC), Turkana, Kenya
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作者 Philip Lomorukai Emekwi Nicholas O. Mariita Patrick Chege Kariuki 《International Journal of Geosciences》 CAS 2024年第3期231-245,共15页
Geothermal is a clean energy source that is freely available in the subsurface. The exploitation of this vital resource needs intensive exploration in order to identify and quantify its occurrence. The three parameter... Geothermal is a clean energy source that is freely available in the subsurface. The exploitation of this vital resource needs intensive exploration in order to identify and quantify its occurrence. The three parameters considered when assessing the viability of a geothermal system include;heat source, fractures and fluids. Geological structures are important in transportation of fluids to and from the heat source aiding in recharge of the geothermal system and enhancing productivity. Remote sensing method was applied in mapping the structures at Barrier Volcanic Complex (BVC) by using hill shading technique which utilized four illumination angles of the sun (azimuth) i.e. 45°, 90°, 150°, and 315°, constant elevation of 45° and exaggeration of 10. The data used was Shuttle Radar Topographic Mission (SRTM) Satellite Imagery. ArcGIS Software was used for lineaments delineation and density mapping, PCI Geomatica was used to generate major faults, while Georose and Rockworks 17 were used to generate the rose diagrams. Geological structural analysis was done by delineating lineaments, determining the density distribution of lineaments and finally determining the structural trends of lineaments. The generated major faults in the area and the location of the occurrence of surface manifestations were compared with the generated lineaments. A total of 260 lineaments were generated whereby at 45° there was a total of 60 lineaments, at 90° 95 lineaments, at 150° 61 lineaments, and at 315° 44 lineaments. The results of structural analysis in the area as shown by the rose diagrams indicate an NNE-SSW and N-S trending of structures. In conclusion, the study area is highly fractured as indicated by the presence of numerous lineaments. These lineaments provide good recharge to the geothermal system and enhance the geothermal reservoir in the area. 展开更多
关键词 Geothermal Resource LINEAMENTS Lineaments Density Structural controls
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Contract Mechanism of Water Environment Regulation for Small and Medium Sized Enterprises Based on Optimal Control Theory
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作者 Shuang Zhao Hongbin Gu +2 位作者 Lianfang Xue Dongsheng Wang Bin Huang 《Journal of Water Resource and Protection》 CAS 2024年第7期538-556,共20页
The small and scattered enterprise pattern in the county economy has formed numerous sporadic pollution sources, hindering the centralized treatment of the water environment, increasing the cost and difficulty of trea... The small and scattered enterprise pattern in the county economy has formed numerous sporadic pollution sources, hindering the centralized treatment of the water environment, increasing the cost and difficulty of treatment. How enterprises can make reasonable decisions on their water environment behavior based on the external environment and their own factors is of great significance for scientifically and effectively designing water environment regulation mechanisms. Based on optimal control theory, this study investigates the design of contractual mechanisms for water environmental regulation for small and medium-sized enterprises. The enterprise is regarded as an independent economic entity that can adopt optimal control strategies to maximize its own interests. Based on the participation of multiple subjects including the government, enterprises, and the public, an optimal control strategy model for enterprises under contractual water environmental regulation is constructed using optimal control theory, and a method for calculating the amount of unit pollutant penalties is derived. The water pollutant treatment cost data of a paper company is selected to conduct empirical numerical analysis on the model. The results show that the increase in the probability of government regulation and public participation, as well as the decrease in local government protection for enterprises, can achieve the same regulatory effect while reducing the number of administrative penalties per unit. Finally, the implementation process of contractual water environmental regulation for small and medium-sized enterprises is designed. 展开更多
关键词 Optimal control Theory Small and Medium-Sized Enterprises Water Environment Regulation Contract Mechanism
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Resilience-Oriented Approach to the Control of Ventricular Assist Devices
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作者 Jônatas Cerqueira Dias Jeferson Cerqueira Dias +1 位作者 Milena Victoria de Azevedo Souza Diolino José dos Santos Filho 《Journal of Biomedical Science and Engineering》 2024年第8期137-156,共20页
Context: Advanced heart failure (AHF) poses a global challenge, where heart transplantation is a treatment option but limited by donor scarcity. Proposal: This study aims to enhance the performance of ventricular assi... Context: Advanced heart failure (AHF) poses a global challenge, where heart transplantation is a treatment option but limited by donor scarcity. Proposal: This study aims to enhance the performance of ventricular assist devices (VADs) in the face of adverse events (AEs) using a resilience-based approach. The objective is to develop a method for integrating resilience attributes into VAD control systems, employing dynamic risk analysis and control strategies. Results: The outcomes include a resilient control architecture enabling anticipatory, regenerative, and degenerative actions in response to AEs. A method of applied resilience (MAR) based on dynamic risk management and resilience attribute analysis was proposed. Conclusion: Dynamic integration between medical and technical teams allows continuous adaptation of control systems to meet patient needs over time, improving reliability, safety, and effectiveness of VADs, with potential positive impact on the health of heart failure patients. 展开更多
关键词 Heart Failure Ventricular Assist Devices RESILIENCE Dynamic control
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Mosquito Control, Killing off the Females
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作者 Phi Tran 《Open Journal of Animal Sciences》 2024年第1期14-22,共9页
In addition to causing discomfort, female mosquitoes introduce disease-carrying viruses and bacteria into the bloodstream of their victims. There are numerous publications describing the uses of sugary mosquito baits ... In addition to causing discomfort, female mosquitoes introduce disease-carrying viruses and bacteria into the bloodstream of their victims. There are numerous publications describing the uses of sugary mosquito baits with promising results. Without temperature control measures however, these methods are mainly useful for only nectar-feeding insects, including male mosquitoes, because the warmth of the blood is a condition for the females to locate their meals. The efforts required to keep the baits fresh against the natural spoiling process make them less attractive or impractical to implement. These experiments address these issues by using warm baits of water, sugar, boric acid, and antibiotics. Overnight, the general areas became clear of blood-sucking female mosquitoes while in numbers, the harmless males concentrated into the immediate vicinities. Control vs. experiment protocol established no other logical explanation for this phenomenon other than that females were attracted and killed by the bait. As expected, there was no female mosquito’s activity in these areas. There weren’t many left to do the work. 展开更多
关键词 Mosquitoes Malaria Dengue control TOXIC Sugar Bait ATSB Samples
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Mathematical Modeling and Control Algorithm Development for Bidirectional Power Flow in CCS-CNT System
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作者 Sinqobile Wiseman Nene 《Journal of Power and Energy Engineering》 2024年第9期131-143,共12页
As the demand for more efficient and adaptable power distribution systems intensifies, especially in rural areas, innovative solutions like the Capacitor-Coupled Substation with a Controllable Network Transformer (CCS... As the demand for more efficient and adaptable power distribution systems intensifies, especially in rural areas, innovative solutions like the Capacitor-Coupled Substation with a Controllable Network Transformer (CCS-CNT) are becoming increasingly critical. Traditional power distribution networks, often limited by unidirectional flow capabilities and inflexibility, struggle to meet the complex demands of modern energy systems. The CCS-CNT system offers a transformative approach by enabling bidirectional power flow between high-voltage transmission lines and local distribution networks, a feature that is essential for integrating renewable energy sources and ensuring reliable electrification in underserved regions. This paper presents a detailed mathematical representation of power flow within the CCS-CNT system, emphasizing the control of both active and reactive power through the adjustment of voltage levels and phase angles. A control algorithm is developed to dynamically manage power flow, ensuring optimal performance by minimizing losses and maintaining voltage stability across the network. The proposed CCS-CNT system demonstrates significant potential in enhancing the efficiency and reliability of power distribution, making it particularly suited for rural electrification and other applications where traditional methods fall short. The findings underscore the system's capability to adapt to varying operational conditions, offering a robust solution for modern power distribution challenges. 展开更多
关键词 Capacitor Couple Substation Ferroresonance Power Flow control controllable Network controller Capacitor-Coupled Substation Incorporating controllable Network Transformer (CCS-CNT) System System Modeling
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