Fish farming,a potential activity for the production of protein with high nutritional value,has emerged as a substantial source of income in the modern world.The degradation of natural materials uses oxygen to reduce ...Fish farming,a potential activity for the production of protein with high nutritional value,has emerged as a substantial source of income in the modern world.The degradation of natural materials uses oxygen to reduce them below the life-support stage.A huge area with an excessive amount of water swamp for oxygen exchange makes for the ideal ecosphere for fish farming,yet the mussel population may grow swiftly in a really modest water swapping farm producing a lot of feed.In this study,we examine the dynamics and chaotic behavior of a fish farm model containing populations of nutrients and mussels with different kernels insight of fractal-fractional operator.We examined the positively invariant area as well as demonstrate positive,bounded solutions of the model.We also show the equilibrium states for the occurrence and extinction of species.We prove the existence and uniqueness of positive solutions through fixed-point theorems and verified the Ulam–Hyers stability for proposed model.To study the impact of the fractional operator through computational simulations,results are generated employing a two-step Lagrange polynomial in the generalized version for the various kernels,which include the power-law and Mittag–Leffler kernel.We develop some numerical simulations to test our theoretical conclusions with chaotic behavior at different fractional-order values.展开更多
Wake effects in large-scalewind farms significantly reduce energy capture efficiency.ActiveWakeControl(AWC),particularly through intentional yaw misalignment of upstream turbines,has emerged as a promising strategy to...Wake effects in large-scalewind farms significantly reduce energy capture efficiency.ActiveWakeControl(AWC),particularly through intentional yaw misalignment of upstream turbines,has emerged as a promising strategy to mitigate these losses by redirecting wakes away from downstream turbines.However,the effectiveness of yaw-based AWC is highly dependent on the accuracy of the underlying wake prediction models,which often require site-specific adjustments to reflect local atmospheric conditions and turbine characteristics.This paper presents an integrated,data-driven framework tomaximize wind farmpower output.Themethodology consists of three key stages.First,a practical simulation-assisted matching method is developed to estimate the True North Alignment(TNA)of each turbine using historical Supervisory Control and Data Acquisition(SCADA)data,resolving a common source of operational uncertainty.Second,key wake expansion parameters of the Floris engineering wake model are calibrated using site-specific SCADA power data,tailoring the model to the JibeiWind Farm in China.Finally,using this calibrated model,the derivative-free solver NOMAD is employed to determine the optimal yaw angle settings for an 11-turbine cluster under various wind conditions.Simulation studies,based on real operational scenarios,demonstrate the effectiveness of the proposed framework.The optimized yaw control strategies achieved total power output gains of up to 5.4%compared to the baseline zero-yaw operation under specific wake-inducing conditions.Crucially,the analysis reveals that using the site-specific calibrated model for optimization yields substantially better results than using a model with generic parameters,providing an additional power gain of up to 1.43%in tested scenarios.These findings underscore the critical importance of TNA estimation and site-specific model calibration for developing effective AWC strategies.The proposed integrated approach provides a robust and practical workflow for designing and pre-validating yaw control settings,offering a valuable tool for enhancing the economic performance of wind farms.展开更多
To ensure the stable operation of power systems with large proportions of wind power,China has published a series of national,industry,and enterprise standards for wind power.The increase in the number of standards an...To ensure the stable operation of power systems with large proportions of wind power,China has published a series of national,industry,and enterprise standards for wind power.The increase in the number of standards and the expansion of their application scope have given rise to a situation where multiple standards overlap and conflict with regard to the establishment of models and their applicability,resulting in unclear standard application scenarios.Therefore,it is imperative to analyze the development of wind-turbine and wind-farm modeling,along with the relevant standards.This paper presents the methods for wind-turbine modeling,the equivalent model of wind farms based on the general model of wind turbines,and the technical provisions and application scenarios involved in the relevant domestic and international standards.The adaptability of the relevant standards is examined.The results of this study are helpful for advancing wind power generation in China and ensuring the safe and stable operation of large-scale wind power systems.展开更多
In this paper,we analyze the dynamical behavior of fish farm model related to Atangana-Baleanu derivative of arbitrary order.The rnodel is constituted with the group of non-linear differential equations having nutrien...In this paper,we analyze the dynamical behavior of fish farm model related to Atangana-Baleanu derivative of arbitrary order.The rnodel is constituted with the group of non-linear differential equations having nutrients,fish and mussel.We have included discrete kind gestational delay of fish.The solution of fish farm model is determined by employing homotopy analysis transforms method(HATM).Existence of and uniqueness of solution are studied through Picard-Lindelof approach.The influence of order of new non-integer order derivative on nutrients,fish and mussel is discussed.The complete study reveals that the outer food supplies manage the behavior of the model.Moreover,to show the outcomes of the study,some numerical results are demonstrated through graphs.展开更多
The reform in water pricing plays a critical role in agricultural production, which is believed to have great water savings potential. We consider eliminating irrigation subsidies as a simulation and conduct a compara...The reform in water pricing plays a critical role in agricultural production, which is believed to have great water savings potential. We consider eliminating irrigation subsidies as a simulation and conduct a comparative evaluation between the water parallel pricing system （WPPS） and the water pricing system （WPS）, which are incorporated into two computable general equilibrium （CGE） models, respectively. The results prove that, compared with WPPS, WPS would contribute higher capacities for water savings with more farming imports and less loss in farming output; households in rural and urban areas would benefit from more income and food consumption, which would be matched by increasing farming imports. A policy recommendation is that eliminating the irrigation subsidy should pay more concerns on alleviating the negative effects on farming outputs. Moreover, improvements in agricultural labor mobility and water demand elasticity are needed to enable more focus on the water conservation policy, particularly in WPS.展开更多
Wind speed dependences on different areas in a wind farm have influences on security and economic operation in power system.In order to simulate the correlation of wind speed series between different positions,this pa...Wind speed dependences on different areas in a wind farm have influences on security and economic operation in power system.In order to simulate the correlation of wind speed series between different positions,this paper applies Copula function and rank correlation matrix methods to measure the coherence of wind speed in a wind farm.The correlated wind sample space is established.According to active power output characteristics of wind turbines,the polymerization model in a wind farm can be achieved.Monte Carlo optimal power flow is applied to IEEE-30 and IEEE-300 bus systems based on the principle of energy saving dispatching.The study shows that the accuracy of outputs is improved,thus reducing the fluctuation ranges in unit generating costs and power flow in branches while considering wind speed polymerization.This approach provides a new method to improve the effectiveness of energy saving dispatching and system operation arrangement.Results have been tested to be effective.展开更多
文摘Fish farming,a potential activity for the production of protein with high nutritional value,has emerged as a substantial source of income in the modern world.The degradation of natural materials uses oxygen to reduce them below the life-support stage.A huge area with an excessive amount of water swamp for oxygen exchange makes for the ideal ecosphere for fish farming,yet the mussel population may grow swiftly in a really modest water swapping farm producing a lot of feed.In this study,we examine the dynamics and chaotic behavior of a fish farm model containing populations of nutrients and mussels with different kernels insight of fractal-fractional operator.We examined the positively invariant area as well as demonstrate positive,bounded solutions of the model.We also show the equilibrium states for the occurrence and extinction of species.We prove the existence and uniqueness of positive solutions through fixed-point theorems and verified the Ulam–Hyers stability for proposed model.To study the impact of the fractional operator through computational simulations,results are generated employing a two-step Lagrange polynomial in the generalized version for the various kernels,which include the power-law and Mittag–Leffler kernel.We develop some numerical simulations to test our theoretical conclusions with chaotic behavior at different fractional-order values.
基金the Science and Technology Project of China South Power Grid Co., Ltd. under Grant No. 036000KK52222044 (GDKJXM20222430).
文摘Wake effects in large-scalewind farms significantly reduce energy capture efficiency.ActiveWakeControl(AWC),particularly through intentional yaw misalignment of upstream turbines,has emerged as a promising strategy to mitigate these losses by redirecting wakes away from downstream turbines.However,the effectiveness of yaw-based AWC is highly dependent on the accuracy of the underlying wake prediction models,which often require site-specific adjustments to reflect local atmospheric conditions and turbine characteristics.This paper presents an integrated,data-driven framework tomaximize wind farmpower output.Themethodology consists of three key stages.First,a practical simulation-assisted matching method is developed to estimate the True North Alignment(TNA)of each turbine using historical Supervisory Control and Data Acquisition(SCADA)data,resolving a common source of operational uncertainty.Second,key wake expansion parameters of the Floris engineering wake model are calibrated using site-specific SCADA power data,tailoring the model to the JibeiWind Farm in China.Finally,using this calibrated model,the derivative-free solver NOMAD is employed to determine the optimal yaw angle settings for an 11-turbine cluster under various wind conditions.Simulation studies,based on real operational scenarios,demonstrate the effectiveness of the proposed framework.The optimized yaw control strategies achieved total power output gains of up to 5.4%compared to the baseline zero-yaw operation under specific wake-inducing conditions.Crucially,the analysis reveals that using the site-specific calibrated model for optimization yields substantially better results than using a model with generic parameters,providing an additional power gain of up to 1.43%in tested scenarios.These findings underscore the critical importance of TNA estimation and site-specific model calibration for developing effective AWC strategies.The proposed integrated approach provides a robust and practical workflow for designing and pre-validating yaw control settings,offering a valuable tool for enhancing the economic performance of wind farms.
基金supported in part by the Joint Research Fund in Smart Grid (U1966208) under a cooperative agreement between the National Natural Science Foundation of China (NSFC) and State Grid Corporation of China (SGCC)
文摘To ensure the stable operation of power systems with large proportions of wind power,China has published a series of national,industry,and enterprise standards for wind power.The increase in the number of standards and the expansion of their application scope have given rise to a situation where multiple standards overlap and conflict with regard to the establishment of models and their applicability,resulting in unclear standard application scenarios.Therefore,it is imperative to analyze the development of wind-turbine and wind-farm modeling,along with the relevant standards.This paper presents the methods for wind-turbine modeling,the equivalent model of wind farms based on the general model of wind turbines,and the technical provisions and application scenarios involved in the relevant domestic and international standards.The adaptability of the relevant standards is examined.The results of this study are helpful for advancing wind power generation in China and ensuring the safe and stable operation of large-scale wind power systems.
文摘In this paper,we analyze the dynamical behavior of fish farm model related to Atangana-Baleanu derivative of arbitrary order.The rnodel is constituted with the group of non-linear differential equations having nutrients,fish and mussel.We have included discrete kind gestational delay of fish.The solution of fish farm model is determined by employing homotopy analysis transforms method(HATM).Existence of and uniqueness of solution are studied through Picard-Lindelof approach.The influence of order of new non-integer order derivative on nutrients,fish and mussel is discussed.The complete study reveals that the outer food supplies manage the behavior of the model.Moreover,to show the outcomes of the study,some numerical results are demonstrated through graphs.
基金National Natural Science Foundation of China(41271547,41501604 and 41271546)the 57th China Postdoctoral Science Foundation(2015M571109)
文摘The reform in water pricing plays a critical role in agricultural production, which is believed to have great water savings potential. We consider eliminating irrigation subsidies as a simulation and conduct a comparative evaluation between the water parallel pricing system （WPPS） and the water pricing system （WPS）, which are incorporated into two computable general equilibrium （CGE） models, respectively. The results prove that, compared with WPPS, WPS would contribute higher capacities for water savings with more farming imports and less loss in farming output; households in rural and urban areas would benefit from more income and food consumption, which would be matched by increasing farming imports. A policy recommendation is that eliminating the irrigation subsidy should pay more concerns on alleviating the negative effects on farming outputs. Moreover, improvements in agricultural labor mobility and water demand elasticity are needed to enable more focus on the water conservation policy, particularly in WPS.
文摘Wind speed dependences on different areas in a wind farm have influences on security and economic operation in power system.In order to simulate the correlation of wind speed series between different positions,this paper applies Copula function and rank correlation matrix methods to measure the coherence of wind speed in a wind farm.The correlated wind sample space is established.According to active power output characteristics of wind turbines,the polymerization model in a wind farm can be achieved.Monte Carlo optimal power flow is applied to IEEE-30 and IEEE-300 bus systems based on the principle of energy saving dispatching.The study shows that the accuracy of outputs is improved,thus reducing the fluctuation ranges in unit generating costs and power flow in branches while considering wind speed polymerization.This approach provides a new method to improve the effectiveness of energy saving dispatching and system operation arrangement.Results have been tested to be effective.
