Contrary to the approach in judicial practice,Paragraph 1,Article 153,of the Civil Code of the People’s Republic of China,as a rule of invalidity for violating mandatory provisions,does not adopt a dichotomy towards ...Contrary to the approach in judicial practice,Paragraph 1,Article 153,of the Civil Code of the People’s Republic of China,as a rule of invalidity for violating mandatory provisions,does not adopt a dichotomy towards mandatory provisions with effectiveness and administrative characteristics,yet it maintains the legislative philosophy of differentiation.It leaves unspecified whether mandatory provisions that do not explicitly render a juristic act invalid impact the act’s validity,entrusting this determination to the discretion of judges on a case-by-case basis.When judges,under the authority of Paragraph 1,Article 153 of the Civil Code,explore the normative intent of mandatory provisions to assess their effect on the validity of juristic acts,they should engage in legal policy analysis centered on consequence-based argumentation to overcome the limitations of norm typological analysis.This analysis employs a reasoning model predicated on the normative purpose,utilizing a consequencefocused interpretative approach for formulating and arguing propositions of rules applicable to pending cases,thereby arriving at case-specific conclusions.Since the invalidation of juristic acts serves as an auxiliary regulatory tool for the state economy and society,a consequence-oriented interpretation needs to be based on the idea of mutual instrumentalization of public and private laws.This entails predicting the outcomes of negating the validity of a juristic act in industrial regulatory scenarios and assessing these outcomes within the framework of public and private regulatory instruments.展开更多
We think we should use basic return rate of industry to measure the opportunity cost of capital and use the rule of Maximum NPV (Net Present Value) to modify the wrong solution in the book.
Enterprise regulations and rules play a major role in corporate governance.However,in recent years,a large number of enterprise regulations and rules were illegal and were thus annulled by the court,and enterprises be...Enterprise regulations and rules play a major role in corporate governance.However,in recent years,a large number of enterprise regulations and rules were illegal and were thus annulled by the court,and enterprises bear related liability to pay compensations.The author analyzed and discussed the predicament of legitimacy in enterprise rules and regulations step by step in three aspects including the legal connotation of enterprise rules and regulations,legitimacy dilemma in the enterprise rules and regulations,measures should be taken by enterprises under the current law framework.The paper aims to provide ideas and thoughts for Chinese enterprises to overcome the legitimacy dilemma of enterprise rules and regulations and give full play to their important roles in corporation governance.展开更多
Pampus argenteus and Pampus chinensis form the high-value demersal Pomfret fishery of Bangladesh.But,due to a monotonic decline in catches over the last five years,it is essential to explore the current stock status c...Pampus argenteus and Pampus chinensis form the high-value demersal Pomfret fishery of Bangladesh.But,due to a monotonic decline in catches over the last five years,it is essential to explore the current stock status concerning the removal rate to ensure the sustainability of this fishery.Therefore,given the reliability and minimal data requirements,this study employed an extended Bayesian State-Space Surplus Production Model,JABBA(Just Another Bayesian Biomass Assessment),to assess the stock rigorously.The results revealed that the stock biomass of the Pomfret fishery in the final year of the time series is significantly lower than BMSY,the biomass required to produce MSY.Consequently,this study recommends a yearly catch limit(TAC)of 10,000 metric tons to prevent further depletion of the stock biomass.Furthermore,to avoid growth overfishing by allowing all immature fishes to reproduce at least once before being caught,this study also calculated the optimum length(Lopt)for catch for both species at which biologically maximum yield and revenue can be obtained.The estimated Lopt is 25 cm for P.argenteus and 30 cm for P.chinensis,and not to capture fishes with lengths lower than these limits,this study further calculated the minimum mesh size limits for gill and set bag nets is 7.5 cm.Though the mesh size regulation was estimated using length-based reference points derived from an empirical equation,this regulation can be used as an associate reference point when TAC is applied to assure the sustainability of this fishery.展开更多
The combined influence of nonlinearity and dilation on slope stability was evaluated using the upper-bound limit analysis theorem.The mechanism of slope collapse was analyzed by dividing it into arbitrary discrete soi...The combined influence of nonlinearity and dilation on slope stability was evaluated using the upper-bound limit analysis theorem.The mechanism of slope collapse was analyzed by dividing it into arbitrary discrete soil blocks with the nonlinear Mohr–Coulomb failure criterion and nonassociated flow rule.The multipoint tangent(multi-tangent) technique was used to analyze the slope stability by linearizing the nonlinear failure criterion.A general expression for the slope safety factor was derived based on the virtual work principle and the strength reduction technique,and the global slope safety factor can be obtained by the optimization method of nonlinear sequential quadratic programming.The results show better agreement with previous research result when the nonlinear failure criterion reduces to a linear failure criterion or the non-associated flow rule reduces to an associated flow rule,which demonstrates the rationality of the presented method.Slope safety factors calculated by the multi-tangent inclined-slices technique were smaller than those obtained by the traditional single-tangent inclined-slices technique.The results show that the multi-tangent inclined-slices technique is a safe and effective method of slope stability limit analysis.The combined effect of nonlinearity and dilation on slope stability was analyzed,and the parameter analysis indicates that nonlinearity and dilation have significant influence on the result of slope stability analysis.展开更多
Allowable levels for pesticide residues in foods, known as tolerances in the US and as maximum residue limits (MRLs) in much of the world, are widely yet inappropriately perceived as levels of safety concern. A nove...Allowable levels for pesticide residues in foods, known as tolerances in the US and as maximum residue limits (MRLs) in much of the world, are widely yet inappropriately perceived as levels of safety concern. A novel approach to develop scientifically defensible levels of safety concern is presented and an example to determine acute and chronic pesticide food safety standard (PFSS) levels for the fungicide captan on strawberries is provided. Using this approach, the chronic PFSS level for captan on strawberries was determined to be 2 000 mg kg-1 and the acute PFSS level was determined to be 250 mg kg-1. Both levels are far above the existing tolerance and MRLs that commonly range from 3 to 20 mg kg-~, and provide evidence that captan residues detected at levels greater than the tolerance or MRLs are not of acute or chronic health concern even though they represent violative residues. The benefits of developing the PFSS approach to serve as a companion to existing tolerances/MRLs include a greater understanding concerning the health significance, if any, from exposure to violative pesticide residues. In addition, the PFSS approach can be universally applied to all potential pesticide residues on all food commodities, can be modified by specific jurisdictions to take into account differences in food consumption practices, and can help prioritize food residue monitoring by identifying the pesticide/commodity combinations of the greatest potential food safety concern and guiding development of field level analytical methods to detect pesticide residues on prioritized pesticide/commodity combinations.展开更多
Soil water is a key factor limiting plant growth in water-limited regions. Without limit of soil water used by plants, soil degradation in the form of soil desiccation is easy to take place in the perennial forestland...Soil water is a key factor limiting plant growth in water-limited regions. Without limit of soil water used by plants, soil degradation in the form of soil desiccation is easy to take place in the perennial forestland and grassland with too higher density or productivity. Soil water resources use limit (SWRUL) is the lowest control limit of soil water resources which is used by plants in those regions. It can be defined as soil water storage within the maximum infiltration depth in which all of soil layers belong to dried soil layers. In this paper, after detailed discussion of characteristics of water resources and the relationship between soil water and plant growth in the Loess Plateau, the definition, quantitative method, and practical applications of SWRUL are introduced. Henceforth, we should strengthen the study of SWRUL and have a better understanding of soil water resources. All those are of great importance for designing effective restoration project and sustainable management of soil water resources in water- limited regions in the future.展开更多
This paper develops a flexible power regulation and limitation strategy of voltage source inverters(VSIs)under unbalanced grid faults.When the classical power theory is used under unbalanced grid faults,the power osci...This paper develops a flexible power regulation and limitation strategy of voltage source inverters(VSIs)under unbalanced grid faults.When the classical power theory is used under unbalanced grid faults,the power oscillations and current distortions are inevitable.In the proposed strategy,the extended power theory is introduced to compute the power feedbacks together with the classical power theory.Based on the combination of the classical and extended power theory,the proposed strategy can achieve the sinusoidal current provision and the flexible regulation between three common targets,i.e.,constant active power,balanced current,and constant reactive power.Meanwhile,the proposed strategy is associated with a power limiter,which is capable to keep the currents under the pre-defined threshold and to compute the maximum apparent power for better utilization of the inverter capacity.With this power limiter,the rated inverter capacity is fully used for both the active and reactive power provisions under unbalanced grid faults.Using the proposed power regulation and limitation,the VSI can avoid overcurrent tripping and flexibly regulate its power under unbalanced grid faults.All the conclusions are verified by the real-time hardware-in-loop tests.展开更多
In this paper the relation is derived between quasi-parabolic regulation and the rule of increasing oxygenpotential. Using these rules in Co-O binary system the stability of compounds CoO and Co_3O_4 is examined.
Purpose–In service,the periodic clashes of wheel flat against the rail result in large wheel/rail impact force and high-frequency vibration,leading to severe damage on the wheelset,rail and track structure.This study...Purpose–In service,the periodic clashes of wheel flat against the rail result in large wheel/rail impact force and high-frequency vibration,leading to severe damage on the wheelset,rail and track structure.This study aims to analyze characteristics and dynamic impact law of wheel and rail caused by wheel flat of high-speed trains.Design/methodology/approach–A full-scale high-speed wheel/rail interface test rig was used for the test of the dynamic impact of wheel/rail caused by wheel flat of high-speed train.With wheel flats of different lengths,widths and depths manually set around the rolling circle of the wheel tread,and wheel/rail dynamic impact tests to the flats in the speed range of 0–400 km/h on the rig were conducted.Findings–As the speed goes up,the flat induced the maximum of the wheel/rail dynamic impact force increases rapidly before it reaches its limit at the speed of around 35 km/h.It then goes down gradually as the speed continues to grow.The impact of flat wheel on rail leads to 100–500 Hz middle-frequency vibration,and around 2,000 Hz and 6,000 Hz high-frequency vibration.In case of any wheel flat found during operation,the train speed shall be controlled according to the status of the flat and avoid the running speed of 20 km/h–80 km/h as much as possible.Originality/value–The research can provide a new method to obtain the dynamic impact of wheel/rail caused by wheel flat by a full-scale high-speed wheel/rail interface test rig.The relations among the flat size,the running speed and the dynamic impact are hopefully of reference to the building of speed limits for HSR wheel flat of different degrees.展开更多
As a section of Dodd-Frank Act,the Volcker Rule bans proprietary trading for banking entities.In view of the outcome of financial tsunami,US Congress enacted such legislation to restrict proprietary trading activities...As a section of Dodd-Frank Act,the Volcker Rule bans proprietary trading for banking entities.In view of the outcome of financial tsunami,US Congress enacted such legislation to restrict proprietary trading activities.However,proprietary trading has moved to less-regulated business sectors,such as hedge funds which may increase overall risk,absent market or regulatory restraint.Since the Volker Rule only focus on proprietary trading,it may neglect the significant problems which truly resulted in the serious financial crisis.The Rule also failed to tackle the long-term commitment which is thought to be one major source of banking losses.In addition,given the difficulties of distinguishing proprietary trading from permitted activities,the Volker Rule probably did not fulfil its regulatory function.For the banking entities,it is important to distinguish between proprietary trading and permitted activities.To be effective,new financial regulation must reflect new relationships in the marketplace,but the Volker Rule fails to reflect the financial reality which requires remedial measures.展开更多
The restriction of load power, two-valued regulation characteristic, and interference of several loads are observed in power supply systems with a limited capacity of voltage sources. In this paper, the definition of ...The restriction of load power, two-valued regulation characteristic, and interference of several loads are observed in power supply systems with a limited capacity of voltage sources. In this paper, the definition of regime in an invariant form through different parameters, of changes of transformation ratio and voltage load is grounded for these circuits with two loads. The approach for interpretation of changes or "kinematics" of load regime is presented by using the conformal and hyperbolic plane. To simplify the task and reveal the basic moments of influence of the limited source power, the static regulation characteristics and idealized models of voltage converters are considered. Geometrical interpretation of a simplified model of multichannel power supply system allows basing the definition of operating regime parameters. Results can be useful for electric circuit theory education and for voltage coordinated control of given loads. Non-Euclidean geometry is a new mathematical apparatus in the electric circuit theory, adequately interprets "kinematics" of circuit, and provides a validation for the introduction and definition of the proposed concepts. From the methodological point, the presented approach is applied for a long time in other scientific domains, as mechanics and biology.展开更多
With the use of centre manifold and dynamic system theory, the necessary and sufficient conditions are obtained for the solvabilities of the output regulator problems for the general nonlinear discrete-time system. Th...With the use of centre manifold and dynamic system theory, the necessary and sufficient conditions are obtained for the solvabilities of the output regulator problems for the general nonlinear discrete-time system. This work generalizes and refines the corresponding results by Isidori and Byrnes on the affine nonlinear continuous-time 'system.展开更多
新能源渗透率的提高增加了电网频率控制的复杂度,储能辅助电网调频能在一定程度上缓解该问题,但受储能运行的安全性与经济性约束,要求调频措施更具针对性。文中对此展开研究,提出一种基于频率响应特性的储能辅助电网一次调频方法。首先...新能源渗透率的提高增加了电网频率控制的复杂度,储能辅助电网调频能在一定程度上缓解该问题,但受储能运行的安全性与经济性约束,要求调频措施更具针对性。文中对此展开研究,提出一种基于频率响应特性的储能辅助电网一次调频方法。首先,在储能辅助电网调频模型基础上,选择惯性加下垂的储能辅助电网调频综合控制方法,通过电网频率变化率(rate of change of frequency,RoCoF)、频率偏差与调频需求的关联性分析,设计基于频率响应特性的调频需求分区规则;然后,根据不同调频需求对应的分区判断,对储能有功输出方式进行动态调整,以响应调频需求的不确定性,并在此基础上,针对调频需求与储能出力需求、储能出力强弱与其循环使用寿命间的矛盾关系,通过多目标优化问题的设计与求解来予以平衡;最后,仿真结果验证了所提方法能够在保证电网调频效果的基础上,有效降低储能充放电深度。展开更多
文摘Contrary to the approach in judicial practice,Paragraph 1,Article 153,of the Civil Code of the People’s Republic of China,as a rule of invalidity for violating mandatory provisions,does not adopt a dichotomy towards mandatory provisions with effectiveness and administrative characteristics,yet it maintains the legislative philosophy of differentiation.It leaves unspecified whether mandatory provisions that do not explicitly render a juristic act invalid impact the act’s validity,entrusting this determination to the discretion of judges on a case-by-case basis.When judges,under the authority of Paragraph 1,Article 153 of the Civil Code,explore the normative intent of mandatory provisions to assess their effect on the validity of juristic acts,they should engage in legal policy analysis centered on consequence-based argumentation to overcome the limitations of norm typological analysis.This analysis employs a reasoning model predicated on the normative purpose,utilizing a consequencefocused interpretative approach for formulating and arguing propositions of rules applicable to pending cases,thereby arriving at case-specific conclusions.Since the invalidation of juristic acts serves as an auxiliary regulatory tool for the state economy and society,a consequence-oriented interpretation needs to be based on the idea of mutual instrumentalization of public and private laws.This entails predicting the outcomes of negating the validity of a juristic act in industrial regulatory scenarios and assessing these outcomes within the framework of public and private regulatory instruments.
文摘We think we should use basic return rate of industry to measure the opportunity cost of capital and use the rule of Maximum NPV (Net Present Value) to modify the wrong solution in the book.
文摘Enterprise regulations and rules play a major role in corporate governance.However,in recent years,a large number of enterprise regulations and rules were illegal and were thus annulled by the court,and enterprises bear related liability to pay compensations.The author analyzed and discussed the predicament of legitimacy in enterprise rules and regulations step by step in three aspects including the legal connotation of enterprise rules and regulations,legitimacy dilemma in the enterprise rules and regulations,measures should be taken by enterprises under the current law framework.The paper aims to provide ideas and thoughts for Chinese enterprises to overcome the legitimacy dilemma of enterprise rules and regulations and give full play to their important roles in corporation governance.
文摘Pampus argenteus and Pampus chinensis form the high-value demersal Pomfret fishery of Bangladesh.But,due to a monotonic decline in catches over the last five years,it is essential to explore the current stock status concerning the removal rate to ensure the sustainability of this fishery.Therefore,given the reliability and minimal data requirements,this study employed an extended Bayesian State-Space Surplus Production Model,JABBA(Just Another Bayesian Biomass Assessment),to assess the stock rigorously.The results revealed that the stock biomass of the Pomfret fishery in the final year of the time series is significantly lower than BMSY,the biomass required to produce MSY.Consequently,this study recommends a yearly catch limit(TAC)of 10,000 metric tons to prevent further depletion of the stock biomass.Furthermore,to avoid growth overfishing by allowing all immature fishes to reproduce at least once before being caught,this study also calculated the optimum length(Lopt)for catch for both species at which biologically maximum yield and revenue can be obtained.The estimated Lopt is 25 cm for P.argenteus and 30 cm for P.chinensis,and not to capture fishes with lengths lower than these limits,this study further calculated the minimum mesh size limits for gill and set bag nets is 7.5 cm.Though the mesh size regulation was estimated using length-based reference points derived from an empirical equation,this regulation can be used as an associate reference point when TAC is applied to assure the sustainability of this fishery.
基金Projects(51208522,51478477)supported by the National Natural Science Foundation of ChinaProject(2012122033)supported by the Guizhou Provincial Department of Transportation Foundation,ChinaProject(CX2015B049)supported by the Scientific Research Innovation Project of Hunan Province,China
文摘The combined influence of nonlinearity and dilation on slope stability was evaluated using the upper-bound limit analysis theorem.The mechanism of slope collapse was analyzed by dividing it into arbitrary discrete soil blocks with the nonlinear Mohr–Coulomb failure criterion and nonassociated flow rule.The multipoint tangent(multi-tangent) technique was used to analyze the slope stability by linearizing the nonlinear failure criterion.A general expression for the slope safety factor was derived based on the virtual work principle and the strength reduction technique,and the global slope safety factor can be obtained by the optimization method of nonlinear sequential quadratic programming.The results show better agreement with previous research result when the nonlinear failure criterion reduces to a linear failure criterion or the non-associated flow rule reduces to an associated flow rule,which demonstrates the rationality of the presented method.Slope safety factors calculated by the multi-tangent inclined-slices technique were smaller than those obtained by the traditional single-tangent inclined-slices technique.The results show that the multi-tangent inclined-slices technique is a safe and effective method of slope stability limit analysis.The combined effect of nonlinearity and dilation on slope stability was analyzed,and the parameter analysis indicates that nonlinearity and dilation have significant influence on the result of slope stability analysis.
基金the Chilean Government and the National Commission for Scientific and Technological Research (CONICYT) for supporting this work through the Becas Chile Scholarships
文摘Allowable levels for pesticide residues in foods, known as tolerances in the US and as maximum residue limits (MRLs) in much of the world, are widely yet inappropriately perceived as levels of safety concern. A novel approach to develop scientifically defensible levels of safety concern is presented and an example to determine acute and chronic pesticide food safety standard (PFSS) levels for the fungicide captan on strawberries is provided. Using this approach, the chronic PFSS level for captan on strawberries was determined to be 2 000 mg kg-1 and the acute PFSS level was determined to be 250 mg kg-1. Both levels are far above the existing tolerance and MRLs that commonly range from 3 to 20 mg kg-~, and provide evidence that captan residues detected at levels greater than the tolerance or MRLs are not of acute or chronic health concern even though they represent violative residues. The benefits of developing the PFSS approach to serve as a companion to existing tolerances/MRLs include a greater understanding concerning the health significance, if any, from exposure to violative pesticide residues. In addition, the PFSS approach can be universally applied to all potential pesticide residues on all food commodities, can be modified by specific jurisdictions to take into account differences in food consumption practices, and can help prioritize food residue monitoring by identifying the pesticide/commodity combinations of the greatest potential food safety concern and guiding development of field level analytical methods to detect pesticide residues on prioritized pesticide/commodity combinations.
文摘Soil water is a key factor limiting plant growth in water-limited regions. Without limit of soil water used by plants, soil degradation in the form of soil desiccation is easy to take place in the perennial forestland and grassland with too higher density or productivity. Soil water resources use limit (SWRUL) is the lowest control limit of soil water resources which is used by plants in those regions. It can be defined as soil water storage within the maximum infiltration depth in which all of soil layers belong to dried soil layers. In this paper, after detailed discussion of characteristics of water resources and the relationship between soil water and plant growth in the Loess Plateau, the definition, quantitative method, and practical applications of SWRUL are introduced. Henceforth, we should strengthen the study of SWRUL and have a better understanding of soil water resources. All those are of great importance for designing effective restoration project and sustainable management of soil water resources in water- limited regions in the future.
基金This work is supported by the National Key Research and Development Program of China under Project 2021YFB2601600。
文摘This paper develops a flexible power regulation and limitation strategy of voltage source inverters(VSIs)under unbalanced grid faults.When the classical power theory is used under unbalanced grid faults,the power oscillations and current distortions are inevitable.In the proposed strategy,the extended power theory is introduced to compute the power feedbacks together with the classical power theory.Based on the combination of the classical and extended power theory,the proposed strategy can achieve the sinusoidal current provision and the flexible regulation between three common targets,i.e.,constant active power,balanced current,and constant reactive power.Meanwhile,the proposed strategy is associated with a power limiter,which is capable to keep the currents under the pre-defined threshold and to compute the maximum apparent power for better utilization of the inverter capacity.With this power limiter,the rated inverter capacity is fully used for both the active and reactive power provisions under unbalanced grid faults.Using the proposed power regulation and limitation,the VSI can avoid overcurrent tripping and flexibly regulate its power under unbalanced grid faults.All the conclusions are verified by the real-time hardware-in-loop tests.
文摘In this paper the relation is derived between quasi-parabolic regulation and the rule of increasing oxygenpotential. Using these rules in Co-O binary system the stability of compounds CoO and Co_3O_4 is examined.
基金by CHINA RAILWAY Scientific and Technological Research and Development Project(contract no.2015J007-E and 2016J007-H)which the authors hereby express their appreciation.
文摘Purpose–In service,the periodic clashes of wheel flat against the rail result in large wheel/rail impact force and high-frequency vibration,leading to severe damage on the wheelset,rail and track structure.This study aims to analyze characteristics and dynamic impact law of wheel and rail caused by wheel flat of high-speed trains.Design/methodology/approach–A full-scale high-speed wheel/rail interface test rig was used for the test of the dynamic impact of wheel/rail caused by wheel flat of high-speed train.With wheel flats of different lengths,widths and depths manually set around the rolling circle of the wheel tread,and wheel/rail dynamic impact tests to the flats in the speed range of 0–400 km/h on the rig were conducted.Findings–As the speed goes up,the flat induced the maximum of the wheel/rail dynamic impact force increases rapidly before it reaches its limit at the speed of around 35 km/h.It then goes down gradually as the speed continues to grow.The impact of flat wheel on rail leads to 100–500 Hz middle-frequency vibration,and around 2,000 Hz and 6,000 Hz high-frequency vibration.In case of any wheel flat found during operation,the train speed shall be controlled according to the status of the flat and avoid the running speed of 20 km/h–80 km/h as much as possible.Originality/value–The research can provide a new method to obtain the dynamic impact of wheel/rail caused by wheel flat by a full-scale high-speed wheel/rail interface test rig.The relations among the flat size,the running speed and the dynamic impact are hopefully of reference to the building of speed limits for HSR wheel flat of different degrees.
文摘As a section of Dodd-Frank Act,the Volcker Rule bans proprietary trading for banking entities.In view of the outcome of financial tsunami,US Congress enacted such legislation to restrict proprietary trading activities.However,proprietary trading has moved to less-regulated business sectors,such as hedge funds which may increase overall risk,absent market or regulatory restraint.Since the Volker Rule only focus on proprietary trading,it may neglect the significant problems which truly resulted in the serious financial crisis.The Rule also failed to tackle the long-term commitment which is thought to be one major source of banking losses.In addition,given the difficulties of distinguishing proprietary trading from permitted activities,the Volker Rule probably did not fulfil its regulatory function.For the banking entities,it is important to distinguish between proprietary trading and permitted activities.To be effective,new financial regulation must reflect new relationships in the marketplace,but the Volker Rule fails to reflect the financial reality which requires remedial measures.
文摘The restriction of load power, two-valued regulation characteristic, and interference of several loads are observed in power supply systems with a limited capacity of voltage sources. In this paper, the definition of regime in an invariant form through different parameters, of changes of transformation ratio and voltage load is grounded for these circuits with two loads. The approach for interpretation of changes or "kinematics" of load regime is presented by using the conformal and hyperbolic plane. To simplify the task and reveal the basic moments of influence of the limited source power, the static regulation characteristics and idealized models of voltage converters are considered. Geometrical interpretation of a simplified model of multichannel power supply system allows basing the definition of operating regime parameters. Results can be useful for electric circuit theory education and for voltage coordinated control of given loads. Non-Euclidean geometry is a new mathematical apparatus in the electric circuit theory, adequately interprets "kinematics" of circuit, and provides a validation for the introduction and definition of the proposed concepts. From the methodological point, the presented approach is applied for a long time in other scientific domains, as mechanics and biology.
文摘With the use of centre manifold and dynamic system theory, the necessary and sufficient conditions are obtained for the solvabilities of the output regulator problems for the general nonlinear discrete-time system. This work generalizes and refines the corresponding results by Isidori and Byrnes on the affine nonlinear continuous-time 'system.
文摘新能源渗透率的提高增加了电网频率控制的复杂度,储能辅助电网调频能在一定程度上缓解该问题,但受储能运行的安全性与经济性约束,要求调频措施更具针对性。文中对此展开研究,提出一种基于频率响应特性的储能辅助电网一次调频方法。首先,在储能辅助电网调频模型基础上,选择惯性加下垂的储能辅助电网调频综合控制方法,通过电网频率变化率(rate of change of frequency,RoCoF)、频率偏差与调频需求的关联性分析,设计基于频率响应特性的调频需求分区规则;然后,根据不同调频需求对应的分区判断,对储能有功输出方式进行动态调整,以响应调频需求的不确定性,并在此基础上,针对调频需求与储能出力需求、储能出力强弱与其循环使用寿命间的矛盾关系,通过多目标优化问题的设计与求解来予以平衡;最后,仿真结果验证了所提方法能够在保证电网调频效果的基础上,有效降低储能充放电深度。