Diabetes affects every organ in the body and cardiovascular disease accounts for two-thirds of the mortality in the diabetic population.Diabetes-related heart disease occurs in the form of coronary artery disease(CAD)...Diabetes affects every organ in the body and cardiovascular disease accounts for two-thirds of the mortality in the diabetic population.Diabetes-related heart disease occurs in the form of coronary artery disease(CAD),cardiac autonomic neuropathy or diabetic cardiomyopathy(DbCM).The prevalence of cardiac failure is high in the diabetic population and DbCM is a common but underestimated cause of heart failure in diabetes.The pathogenesis of diabetic cardiomyopathy is yet to be clearly defined.Hyperglycemia,dyslipidemia and inflammation are thought to play key roles in the generation of reactive oxygen or nitrogen species which are in turn implicated.The myocardial interstitium undergoes alterations resulting in abnormal contractile function noted in DbCM.In the early stages of the disease diastolic dysfunction is the only abnormality,but systolic dysfunction supervenes in the later stages with impaired left ventricular ejection fraction.Transmitral Doppler echocardiography is usually used to assess diastolic dysfunction,but tissue Doppler Imaging and Cardiac Magnetic Resonance Imaging are being increasingly used recently for early detection of DbCM.The management of DbCM involves improvement in lifestyle,control of glucose and lipid abnormalities,and treatment of hypertension and CAD,if present.The role of vasoactive drugs and antioxidants is being explored.This review discusses the pathophysiology,diagnostic evaluation and management options of DbCM.展开更多
To reach a higher level of autonomy for unmanned combat aerial vehicle(UCAV) in air combat games, this paper builds an autonomous maneuver decision system. In this system,the air combat game is regarded as a Markov pr...To reach a higher level of autonomy for unmanned combat aerial vehicle(UCAV) in air combat games, this paper builds an autonomous maneuver decision system. In this system,the air combat game is regarded as a Markov process, so that the air combat situation can be effectively calculated via Bayesian inference theory. According to the situation assessment result,adaptively adjusts the weights of maneuver decision factors, which makes the objective function more reasonable and ensures the superiority situation for UCAV. As the air combat game is characterized by highly dynamic and a significant amount of uncertainty,to enhance the robustness and effectiveness of maneuver decision results, fuzzy logic is used to build the functions of four maneuver decision factors. Accuracy prediction of opponent aircraft is also essential to ensure making a good decision; therefore, a prediction model of opponent aircraft is designed based on the elementary maneuver method. Finally, the moving horizon optimization strategy is used to effectively model the whole air combat maneuver decision process. Various simulations are performed on typical scenario test and close-in dogfight, the results sufficiently demonstrate the superiority of the designed maneuver decision method.展开更多
Cardiac autonomic neuropathy(CAN)is an often overlooked and common complication of diabetes mellitus.CAN is associated with increased cardiovascular morbidity and mortality.The pathogenesis of CAN is complex and invol...Cardiac autonomic neuropathy(CAN)is an often overlooked and common complication of diabetes mellitus.CAN is associated with increased cardiovascular morbidity and mortality.The pathogenesis of CAN is complex and involves a cascade of pathways activated by hyperglycaemia resulting in neuronal ischaemia and cellular death.In addition,autoimmune and genetic factors are involved in the development of CAN.CAN might be subclinical for several years until the patient develops resting tachycardia,exercise intolerance,postural hypotension,cardiac dysfunction and diabetic cardiomyopathy.During its sub-clinical phase,heart rate variability that is influenced by the balance between parasympathetic and sympathetic tones can help in detecting CAN before the disease is symptomatic.Newer imaging techniques(such as scintigraphy)have allowed earlier detection of CAN in the pre-clinical phase and allowed better assessment of the sympathetic nervous system.One of the main difficulties in CAN research is the lack of a universally accepted definition of CAN;however,the Toronto Consensus Panel on Diabetic Neuropathy has recently issued guidance for the diagnosis and staging of CAN,and also proposed screening for CAN in patients with diabetes mellitus.A major challenge,however,is the lack of specific treatment to slow the progression or prevent the development of CAN.Lifestyle changes,improved metabolic control might prevent or slow the progression of CAN.Reversal will require combination of these treatments with new targeted therapeutic approaches.The aim of this article is to review the latest evidence regarding the epidemiology,pathogenesis,manifestations,diagnosis and treatment for CAN.展开更多
AIM: To investigate the acupuncture-modulated gastric motility and its underlying neural mechanism.METHODS: Intragastric pressure and/or waves of gastric contraction in rats were recorded by intrapyloric balloon and c...AIM: To investigate the acupuncture-modulated gastric motility and its underlying neural mechanism.METHODS: Intragastric pressure and/or waves of gastric contraction in rats were recorded by intrapyloric balloon and changes of gastric motility induced by acupuncture stimulation were compared with the background activity before any stimulation. Gastro-vagal or splanchnic-sympathetic nerves were recorded or cut respectively for investigating the involvement of autonomic nerve pathways. Spinalization experiment was also performed.RESULTS: Acupuncture-stimulation by exciting Aδ and/or C afferent fibers, could only modulate gastric motility. Acupuncture-stimulation on fore- and hind-limbs evoked a moderate gastric motility followed by increased vagus discharges with unchanged sympathetic activity, while the same stimulus to the acupoints in abdomen resulted in reversed effects on gastric motility and autonomic nervous activities. The inhibitory gastric response was completely abolished by splanchnic denervation, but the facilitative gastric response to stimulation of acupoints in limbs was not influenced, which was opposite to the effect when vagotomy was performed. The similar depressive effects were produced by the stimulation at the acupoints homo-segmental to the gastric innervation in the animals with or without spinalization. However, the facilitation induced by the stimulation at the acupoints hetero-segmental to the gastric innervation was not observed in the spinalized animals.CONCLUSION: Facilitative effects of stimulating hetero-segmental acupoints are involved in the intact preparation of vagal nerves and spinal cord, while the inhibitory response induced by stimulating homo-segmental acupoints is involved in the intact preparation of sympathetic nerves. Only the acupuncture-stimulation with intensity over the threshold of Aδ and/or C afferent fibers can markedly modulate gastrointestinal motility.展开更多
This article analyzes the current research status and development trend of intelligent technologies for underground metal mines in China, where such technologies are under development for use to develop mineral resour...This article analyzes the current research status and development trend of intelligent technologies for underground metal mines in China, where such technologies are under development for use to develop mineral resources in a safe, efficient, and environmentally friendly manner. We analyze and summarize the research status of underground metal mining technology at home and abroad, including some specific examples of equipment, technology, and applications. We introduce the latest equipment and technolo- gies with independent intellectual property rights for unmanned mining, including intelligent and unmanned control technologies for rock-drilling jumbos, down-the-hole （DTH） drills, underground scrapers, underground mining trucks, and underground charging vehicles. Three basic platforms are used for intelligent and unmanned mining： the positioning and navigation platform, information-acquisition and communication platform, and scheduling and control platform. Unmanned equipment was tested in the Fankou Lead-Zinc Mine in China, and industrial tests on the basic platforms of intelligent and unmanned mining were carried out in the mine. The experiment focused on the intelligent scraper, which can achieve autonomous intelligent driving by relying on a wireless communication system, location and navigation system, and data-acquisition system. These industrial experiments indicate that the technol- ogy is feasible. The results show that unmanned mining can promote mining technology in China to an intelligent level and can enhance the core competitive ability of China＇s mining industry.展开更多
As a new software paradigm evolved by the Internet, Internetware brings many challenges for the traditional software development methods and techniques. Though architecture-based component composition （ABC） approach...As a new software paradigm evolved by the Internet, Internetware brings many challenges for the traditional software development methods and techniques. Though architecture-based component composition （ABC） approach is originated in the traditional software paradigm, it supports the engineering of Internetware effectively due to its philosophy, rationales and mechanisms. ABC has three major contributions to the en- gineering of Internetware in detail. First, the feature oriented domain modeling method can structure the ＂disordered＂ ＂software entities＂ to ＂ordered Internetware＂ bottom-up in the problem space. Second, the architecture centric design and analysis method can support the development of self-adaptive Internetware. Third, the component operating platform is a reflective and self-adaptive middleware that not only provides Internetware with a powerful and flexible runtime infrastructure but also enables the self-adaptation of the structure and individual entities of Internetware.展开更多
Intelligent connected vehicles(ICVs) are believed to change people's life in the near future by making the transportation safer,cleaner and more comfortable. Although many prototypes of ICVs have been developed to...Intelligent connected vehicles(ICVs) are believed to change people's life in the near future by making the transportation safer,cleaner and more comfortable. Although many prototypes of ICVs have been developed to prove the concept of autonomous driving and the feasibility of improving traffic efficiency, there still exists a significant gap before achieving mass production of high-level ICVs. The objective of this study is to present an overview of both the state of the art and future perspectives of key technologies that are needed for future ICVs. It is a challenging task to review all related works and predict their future perspectives, especially for such a complex and interdisciplinary area of research. This article is organized to overview the ICV key technologies by answering three questions: what are the milestones in the history of ICVs; what are the electronic components needed for building an ICV platform; and what are the essential algorithms to enable intelligent driving? To answer the first question, the article has reviewed the history and the development milestones of ICVs. For the second question, the recent technology advances in electrical/electronic architecture, sensors, and actuators are presented. For the third question, the article focuses on the algorithms in decision making, as the perception and control algorithm are covered in the development of sensors and actuators. To achieve correct decision-making, there exist two different approaches: the principle-based approach and data-driven approach. The advantages and limitations of both approaches are explained and analyzed. Currently automotive engineers are concerned more with the vehicle platform technology, whereas the academic researchers prefer to focus on theoretical algorithms. However, only by incorporating elements from both worlds can we accelerate the production of high-level ICVs.展开更多
Bio-inspired intelligence is in the spotlight in the field of international artificial intelligence,and unmanned combat aerial vehicle(UCAV),owing to its potential to perform dangerous,repetitive tasks in remote and h...Bio-inspired intelligence is in the spotlight in the field of international artificial intelligence,and unmanned combat aerial vehicle(UCAV),owing to its potential to perform dangerous,repetitive tasks in remote and hazardous,is very promising for the technological leadership of the nation and essential for improving the security of society.On the basis of introduction of bioinspired intelligence and UCAV,a series of new development thoughts on UCAV control are proposed,including artificial brain based high-level autonomous control for UCAV,swarm intelligence based cooperative control for multiple UCAVs,hy-brid swarm intelligence and Bayesian network based situation assessment under complicated combating environments, bio-inspired hardware based high-level autonomous control for UCAV,and meta-heuristic intelligence based heterogeneous cooperative control for multiple UCAVs and unmanned combat ground vehicles(UCGVs).The exact realization of the proposed new development thoughts can enhance the effectiveness of combat,while provide a series of novel breakthroughs for the intelligence,integration and advancement of future UCAV systems.展开更多
PETREL, a winged hybrid-driven underwater glider is a novel and practical marine survey platform which combines the features of legacy underwater glider and conventional AUV （autonomous underwater vehicle）. It can b...PETREL, a winged hybrid-driven underwater glider is a novel and practical marine survey platform which combines the features of legacy underwater glider and conventional AUV （autonomous underwater vehicle）. It can be treated as a multi-rigid-body system with a floating base and a particular hydrodynamic profile. In this paper, theorems on linear and angular momentum are used to establish the dynamic equations of motion of each rigid body and the effect of translational and rotational motion of internal masses on the attitude control are taken into consideration. In addition, due to the unique external shape with fixed wings and deflectable rudders and the dual-drive operation in thrust and glide modes, the approaches of building dynamic model of conventional AUV and hydrodynamic model of submarine are introduced, and the tailored dynamic equations of the hybrid glider are formulated. Moreover, the behaviors of motion in glide and thrust operation are analyzed based on the simulation and the feasibility of the dynamic model is validated by data from lake field trials.展开更多
This paper investigates the use of a virtual synchronous generator(VSG) to improve frequency stability in an autonomous photovoltaic-diesel microgrid with energy storage. VSG control is designed to emulate inertial re...This paper investigates the use of a virtual synchronous generator(VSG) to improve frequency stability in an autonomous photovoltaic-diesel microgrid with energy storage. VSG control is designed to emulate inertial response and damping power via power injection from/to the energy storage system. The effect of a VSG with constant parameters(CP-VSG) on the system frequency is analyzed. Based on the case study, self-tuning algorithms are used to search for optimal parameters during the operation of the VSG in order to minimize the amplitude and rate of change of the frequency variations. The performances of the proposed self-tuning(ST)-VSG, the frequency droop method, and the CP-VSG are evaluated by comparing their effects on attenuating frequency variationsunder load variations. For both simulated and experimental cases, the ST-VSG was found to be more efficient than the other two methods in improving frequency stability.展开更多
文摘Diabetes affects every organ in the body and cardiovascular disease accounts for two-thirds of the mortality in the diabetic population.Diabetes-related heart disease occurs in the form of coronary artery disease(CAD),cardiac autonomic neuropathy or diabetic cardiomyopathy(DbCM).The prevalence of cardiac failure is high in the diabetic population and DbCM is a common but underestimated cause of heart failure in diabetes.The pathogenesis of diabetic cardiomyopathy is yet to be clearly defined.Hyperglycemia,dyslipidemia and inflammation are thought to play key roles in the generation of reactive oxygen or nitrogen species which are in turn implicated.The myocardial interstitium undergoes alterations resulting in abnormal contractile function noted in DbCM.In the early stages of the disease diastolic dysfunction is the only abnormality,but systolic dysfunction supervenes in the later stages with impaired left ventricular ejection fraction.Transmitral Doppler echocardiography is usually used to assess diastolic dysfunction,but tissue Doppler Imaging and Cardiac Magnetic Resonance Imaging are being increasingly used recently for early detection of DbCM.The management of DbCM involves improvement in lifestyle,control of glucose and lipid abnormalities,and treatment of hypertension and CAD,if present.The role of vasoactive drugs and antioxidants is being explored.This review discusses the pathophysiology,diagnostic evaluation and management options of DbCM.
基金supported by the National Natural Science Foundation of China(61601505)the Aeronautical Science Foundation of China(20155196022)the Shaanxi Natural Science Foundation of China(2016JQ6050)
文摘To reach a higher level of autonomy for unmanned combat aerial vehicle(UCAV) in air combat games, this paper builds an autonomous maneuver decision system. In this system,the air combat game is regarded as a Markov process, so that the air combat situation can be effectively calculated via Bayesian inference theory. According to the situation assessment result,adaptively adjusts the weights of maneuver decision factors, which makes the objective function more reasonable and ensures the superiority situation for UCAV. As the air combat game is characterized by highly dynamic and a significant amount of uncertainty,to enhance the robustness and effectiveness of maneuver decision results, fuzzy logic is used to build the functions of four maneuver decision factors. Accuracy prediction of opponent aircraft is also essential to ensure making a good decision; therefore, a prediction model of opponent aircraft is designed based on the elementary maneuver method. Finally, the moving horizon optimization strategy is used to effectively model the whole air combat maneuver decision process. Various simulations are performed on typical scenario test and close-in dogfight, the results sufficiently demonstrate the superiority of the designed maneuver decision method.
文摘Cardiac autonomic neuropathy(CAN)is an often overlooked and common complication of diabetes mellitus.CAN is associated with increased cardiovascular morbidity and mortality.The pathogenesis of CAN is complex and involves a cascade of pathways activated by hyperglycaemia resulting in neuronal ischaemia and cellular death.In addition,autoimmune and genetic factors are involved in the development of CAN.CAN might be subclinical for several years until the patient develops resting tachycardia,exercise intolerance,postural hypotension,cardiac dysfunction and diabetic cardiomyopathy.During its sub-clinical phase,heart rate variability that is influenced by the balance between parasympathetic and sympathetic tones can help in detecting CAN before the disease is symptomatic.Newer imaging techniques(such as scintigraphy)have allowed earlier detection of CAN in the pre-clinical phase and allowed better assessment of the sympathetic nervous system.One of the main difficulties in CAN research is the lack of a universally accepted definition of CAN;however,the Toronto Consensus Panel on Diabetic Neuropathy has recently issued guidance for the diagnosis and staging of CAN,and also proposed screening for CAN in patients with diabetes mellitus.A major challenge,however,is the lack of specific treatment to slow the progression or prevent the development of CAN.Lifestyle changes,improved metabolic control might prevent or slow the progression of CAN.Reversal will require combination of these treatments with new targeted therapeutic approaches.The aim of this article is to review the latest evidence regarding the epidemiology,pathogenesis,manifestations,diagnosis and treatment for CAN.
基金Supported by National Natural Science Foundation of China, No. C30100245 National Basic Research 973 Program, No. 2005CB523308
文摘AIM: To investigate the acupuncture-modulated gastric motility and its underlying neural mechanism.METHODS: Intragastric pressure and/or waves of gastric contraction in rats were recorded by intrapyloric balloon and changes of gastric motility induced by acupuncture stimulation were compared with the background activity before any stimulation. Gastro-vagal or splanchnic-sympathetic nerves were recorded or cut respectively for investigating the involvement of autonomic nerve pathways. Spinalization experiment was also performed.RESULTS: Acupuncture-stimulation by exciting Aδ and/or C afferent fibers, could only modulate gastric motility. Acupuncture-stimulation on fore- and hind-limbs evoked a moderate gastric motility followed by increased vagus discharges with unchanged sympathetic activity, while the same stimulus to the acupoints in abdomen resulted in reversed effects on gastric motility and autonomic nervous activities. The inhibitory gastric response was completely abolished by splanchnic denervation, but the facilitative gastric response to stimulation of acupoints in limbs was not influenced, which was opposite to the effect when vagotomy was performed. The similar depressive effects were produced by the stimulation at the acupoints homo-segmental to the gastric innervation in the animals with or without spinalization. However, the facilitation induced by the stimulation at the acupoints hetero-segmental to the gastric innervation was not observed in the spinalized animals.CONCLUSION: Facilitative effects of stimulating hetero-segmental acupoints are involved in the intact preparation of vagal nerves and spinal cord, while the inhibitory response induced by stimulating homo-segmental acupoints is involved in the intact preparation of sympathetic nerves. Only the acupuncture-stimulation with intensity over the threshold of Aδ and/or C afferent fibers can markedly modulate gastrointestinal motility.
文摘This article analyzes the current research status and development trend of intelligent technologies for underground metal mines in China, where such technologies are under development for use to develop mineral resources in a safe, efficient, and environmentally friendly manner. We analyze and summarize the research status of underground metal mining technology at home and abroad, including some specific examples of equipment, technology, and applications. We introduce the latest equipment and technolo- gies with independent intellectual property rights for unmanned mining, including intelligent and unmanned control technologies for rock-drilling jumbos, down-the-hole （DTH） drills, underground scrapers, underground mining trucks, and underground charging vehicles. Three basic platforms are used for intelligent and unmanned mining： the positioning and navigation platform, information-acquisition and communication platform, and scheduling and control platform. Unmanned equipment was tested in the Fankou Lead-Zinc Mine in China, and industrial tests on the basic platforms of intelligent and unmanned mining were carried out in the mine. The experiment focused on the intelligent scraper, which can achieve autonomous intelligent driving by relying on a wireless communication system, location and navigation system, and data-acquisition system. These industrial experiments indicate that the technol- ogy is feasible. The results show that unmanned mining can promote mining technology in China to an intelligent level and can enhance the core competitive ability of China＇s mining industry.
基金This work was supported by the National Basic Research Program of China （973） （Grant No. 2002CB312003） the National Natural Science Foundation of China （Grant Nos. 60233010, 90612011, 90412011, 60403030, 60303004）the Natural Science Foundation of Beijing （Grant No. 4052018）.
文摘As a new software paradigm evolved by the Internet, Internetware brings many challenges for the traditional software development methods and techniques. Though architecture-based component composition （ABC） approach is originated in the traditional software paradigm, it supports the engineering of Internetware effectively due to its philosophy, rationales and mechanisms. ABC has three major contributions to the en- gineering of Internetware in detail. First, the feature oriented domain modeling method can structure the ＂disordered＂ ＂software entities＂ to ＂ordered Internetware＂ bottom-up in the problem space. Second, the architecture centric design and analysis method can support the development of self-adaptive Internetware. Third, the component operating platform is a reflective and self-adaptive middleware that not only provides Internetware with a powerful and flexible runtime infrastructure but also enables the self-adaptation of the structure and individual entities of Internetware.
基金supported by the International Science and Technology Cooperation Program of China(Grant No.2016YFE0102200)the National Natural Science Foundation of China(Grant No.61773234)+1 种基金the National Key R&D Program of China(Grant No.2108YFB0105004)and Beijing Municipal Science and Technology Commission(Grant Nos.D171100005117001&D171100005117002)
文摘Intelligent connected vehicles(ICVs) are believed to change people's life in the near future by making the transportation safer,cleaner and more comfortable. Although many prototypes of ICVs have been developed to prove the concept of autonomous driving and the feasibility of improving traffic efficiency, there still exists a significant gap before achieving mass production of high-level ICVs. The objective of this study is to present an overview of both the state of the art and future perspectives of key technologies that are needed for future ICVs. It is a challenging task to review all related works and predict their future perspectives, especially for such a complex and interdisciplinary area of research. This article is organized to overview the ICV key technologies by answering three questions: what are the milestones in the history of ICVs; what are the electronic components needed for building an ICV platform; and what are the essential algorithms to enable intelligent driving? To answer the first question, the article has reviewed the history and the development milestones of ICVs. For the second question, the recent technology advances in electrical/electronic architecture, sensors, and actuators are presented. For the third question, the article focuses on the algorithms in decision making, as the perception and control algorithm are covered in the development of sensors and actuators. To achieve correct decision-making, there exist two different approaches: the principle-based approach and data-driven approach. The advantages and limitations of both approaches are explained and analyzed. Currently automotive engineers are concerned more with the vehicle platform technology, whereas the academic researchers prefer to focus on theoretical algorithms. However, only by incorporating elements from both worlds can we accelerate the production of high-level ICVs.
基金supported by the National Natural Science Foundation of China(Grant Nos.60975072,60604009)the Aeronautical Science Foundation of China(Grant No.2008ZC01006)+2 种基金Beijing NOVA Program Foundation(Grant No.2007A017)the Fundamental Research Funds for the Central Universities(Grant No.YWF-10-01-A18)the Program for New Century Excellent Talents in University of China(Grant No.NCET-10-0021)
文摘Bio-inspired intelligence is in the spotlight in the field of international artificial intelligence,and unmanned combat aerial vehicle(UCAV),owing to its potential to perform dangerous,repetitive tasks in remote and hazardous,is very promising for the technological leadership of the nation and essential for improving the security of society.On the basis of introduction of bioinspired intelligence and UCAV,a series of new development thoughts on UCAV control are proposed,including artificial brain based high-level autonomous control for UCAV,swarm intelligence based cooperative control for multiple UCAVs,hy-brid swarm intelligence and Bayesian network based situation assessment under complicated combating environments, bio-inspired hardware based high-level autonomous control for UCAV,and meta-heuristic intelligence based heterogeneous cooperative control for multiple UCAVs and unmanned combat ground vehicles(UCGVs).The exact realization of the proposed new development thoughts can enhance the effectiveness of combat,while provide a series of novel breakthroughs for the intelligence,integration and advancement of future UCAV systems.
基金supported by the National Natural Science Foundation of China(Grant Nos. 50835006 and 51005161)the Science & Technology Support Planning Foundation of Tianjin(Grant No. 09ZCKFGX03000)the Natural Science Foundation of Tianjin(Grant No. 09JCZDJC23400)
文摘PETREL, a winged hybrid-driven underwater glider is a novel and practical marine survey platform which combines the features of legacy underwater glider and conventional AUV （autonomous underwater vehicle）. It can be treated as a multi-rigid-body system with a floating base and a particular hydrodynamic profile. In this paper, theorems on linear and angular momentum are used to establish the dynamic equations of motion of each rigid body and the effect of translational and rotational motion of internal masses on the attitude control are taken into consideration. In addition, due to the unique external shape with fixed wings and deflectable rudders and the dual-drive operation in thrust and glide modes, the approaches of building dynamic model of conventional AUV and hydrodynamic model of submarine are introduced, and the tailored dynamic equations of the hybrid glider are formulated. Moreover, the behaviors of motion in glide and thrust operation are analyzed based on the simulation and the feasibility of the dynamic model is validated by data from lake field trials.
基金supported by National High Technology Research and Development Program of China(863Program)(No.2015AA050607)the National key Research and Development Program of China(No.2016YFB0900300)the Science and Technology project of SGCC(No.NYB17201700151)
文摘This paper investigates the use of a virtual synchronous generator(VSG) to improve frequency stability in an autonomous photovoltaic-diesel microgrid with energy storage. VSG control is designed to emulate inertial response and damping power via power injection from/to the energy storage system. The effect of a VSG with constant parameters(CP-VSG) on the system frequency is analyzed. Based on the case study, self-tuning algorithms are used to search for optimal parameters during the operation of the VSG in order to minimize the amplitude and rate of change of the frequency variations. The performances of the proposed self-tuning(ST)-VSG, the frequency droop method, and the CP-VSG are evaluated by comparing their effects on attenuating frequency variationsunder load variations. For both simulated and experimental cases, the ST-VSG was found to be more efficient than the other two methods in improving frequency stability.
