In this paper, the Authors present the designing of power system stabilizer (PSS) and static var compensator (SVC) based on chaos, particle swarm optimization (PSO) and shuffled frog leaping (SFL) Algorithms has been ...In this paper, the Authors present the designing of power system stabilizer (PSS) and static var compensator (SVC) based on chaos, particle swarm optimization (PSO) and shuffled frog leaping (SFL) Algorithms has been presented to improve the power system stability. Single machine infinite bus (SMIB) system with SVC located at the terminal of generator has been considered to evaluate the proposed SVC and PSS controllers. The coefficients of PSS and SVC controller have been optimized by Chaos, PSO and SFL algorithms. Fi-nally the system with proposed controllers is simulated for the special disturbance in input power of genera-tor, and then the dynamic responses of generator have been presented. The simulation results show that the system composed with recommended controller has outstanding operation in fast damping of oscillations of power system and describes an application of Chaos, PSO and SFL algorithms to the problem of designing a Lead-Lag controller used in PSS and SVC in power system.展开更多
Context is a very important concept or term both in SFL and in pragmatics.But it has to be understood differently in the two disciplines.This paper attempts to demonstrate the differences and show that context in the ...Context is a very important concept or term both in SFL and in pragmatics.But it has to be understood differently in the two disciplines.This paper attempts to demonstrate the differences and show that context in the two different disciplines can be complementary to each other based on the differences.展开更多
There are quite a few students in China are incompetent to organize text in a cohesive and coherent way in English writ-ing. This essay gives a general introduction of systemic functional linguistics theory, aiming at...There are quite a few students in China are incompetent to organize text in a cohesive and coherent way in English writ-ing. This essay gives a general introduction of systemic functional linguistics theory, aiming at emphasizing the feasibility of apply-ing SFL as a tool to improve the English writing proficiency of students in China.展开更多
Sulfur-free lignin(SFL),a byproduct of the corn ethanol industry,effectively improves soil strength;however,its inherent solubility limits saline soil treatment in dry-wet environments.To solve this problem,this paper...Sulfur-free lignin(SFL),a byproduct of the corn ethanol industry,effectively improves soil strength;however,its inherent solubility limits saline soil treatment in dry-wet environments.To solve this problem,this paper proposes the selection of a granular SFL(GSFL)with a relatively large particle size,but with its chemical properties retained,to replace the conventional powdered SFL(PSFL).Among the processes of water-induced erosion failure of earthen structures,disintegration is commonly deemed the primary cause.Therefore,the disintegration characteristics of both PSFL-and GSFL-modified soils with 0%,5%,7%,10%,and 12%dosages were tested under dry-wet conditions.Moreover,several physicochemical properties,including the particle size distribution,bound water content,pH value,cation exchange capacity,functional groups,and microstructure,were explored.The results revealed that the water stability of the GSFL-modified soils was greater than that of the PSFL-modified soils.All of the PSFL-modified soils and natural soil completely disintegrated at the first immersion stage,whereas the GSFL-modified soils resisted 7 dry-wet cycles,notably at the 10%dosage.Microscopic analysis revealed that the SFL particle size affected mainly the cementation strength and microstructural homogeneity.Both the GSFL and PSFL particles strengthened the intergranular cementation through ion exchange,electrostatic interactions,and reinforcement effects.However,the PSFL preferentially filled the intragranular pores,causing a nonuniform microstructural arrangement and ineffectively enhancing the disintegration resistance of the saline soil.This preliminary study suggests that the particle size of a soil modifier may affect certain properties of the modified soil,necessitating future focused research.展开更多
文摘In this paper, the Authors present the designing of power system stabilizer (PSS) and static var compensator (SVC) based on chaos, particle swarm optimization (PSO) and shuffled frog leaping (SFL) Algorithms has been presented to improve the power system stability. Single machine infinite bus (SMIB) system with SVC located at the terminal of generator has been considered to evaluate the proposed SVC and PSS controllers. The coefficients of PSS and SVC controller have been optimized by Chaos, PSO and SFL algorithms. Fi-nally the system with proposed controllers is simulated for the special disturbance in input power of genera-tor, and then the dynamic responses of generator have been presented. The simulation results show that the system composed with recommended controller has outstanding operation in fast damping of oscillations of power system and describes an application of Chaos, PSO and SFL algorithms to the problem of designing a Lead-Lag controller used in PSS and SVC in power system.
文摘Context is a very important concept or term both in SFL and in pragmatics.But it has to be understood differently in the two disciplines.This paper attempts to demonstrate the differences and show that context in the two different disciplines can be complementary to each other based on the differences.
文摘There are quite a few students in China are incompetent to organize text in a cohesive and coherent way in English writ-ing. This essay gives a general introduction of systemic functional linguistics theory, aiming at emphasizing the feasibility of apply-ing SFL as a tool to improve the English writing proficiency of students in China.
基金funded by the National Natural Science Foundation of China(Grant Nos.42330708 and 42302329).
文摘Sulfur-free lignin(SFL),a byproduct of the corn ethanol industry,effectively improves soil strength;however,its inherent solubility limits saline soil treatment in dry-wet environments.To solve this problem,this paper proposes the selection of a granular SFL(GSFL)with a relatively large particle size,but with its chemical properties retained,to replace the conventional powdered SFL(PSFL).Among the processes of water-induced erosion failure of earthen structures,disintegration is commonly deemed the primary cause.Therefore,the disintegration characteristics of both PSFL-and GSFL-modified soils with 0%,5%,7%,10%,and 12%dosages were tested under dry-wet conditions.Moreover,several physicochemical properties,including the particle size distribution,bound water content,pH value,cation exchange capacity,functional groups,and microstructure,were explored.The results revealed that the water stability of the GSFL-modified soils was greater than that of the PSFL-modified soils.All of the PSFL-modified soils and natural soil completely disintegrated at the first immersion stage,whereas the GSFL-modified soils resisted 7 dry-wet cycles,notably at the 10%dosage.Microscopic analysis revealed that the SFL particle size affected mainly the cementation strength and microstructural homogeneity.Both the GSFL and PSFL particles strengthened the intergranular cementation through ion exchange,electrostatic interactions,and reinforcement effects.However,the PSFL preferentially filled the intragranular pores,causing a nonuniform microstructural arrangement and ineffectively enhancing the disintegration resistance of the saline soil.This preliminary study suggests that the particle size of a soil modifier may affect certain properties of the modified soil,necessitating future focused research.
