In this paper,given the shortcomings of jellyfish search algorithmwith low search ability in the early stage and easy to fall into local optimal solution,this paper introduces adaptive weight function and elite strate...In this paper,given the shortcomings of jellyfish search algorithmwith low search ability in the early stage and easy to fall into local optimal solution,this paper introduces adaptive weight function and elite strategy,improving the global search scope in the early stage and the ability to refine the local development in the later stage.In the numerical study,the benchmark problem of dimensional optimization with a 10-bar truss structure and simultaneous dimensional shape optimization with a 15-bar truss structure is adopted,and the corresponding penalty method is used for constraint treatment.The test results show that the improved jellyfish search algorithm can provide better truss sections as well as weights.Because when the steel main truss of the large-span covered bridge is lifted,the site is limited and the large lifting equipment cannot enter the site,and the original structure does not meet the problem of stress concentration and large deformation of the bolt group,so the spreader is used to lift,and the improved jellyfish search algorithm is introduced into the design optimization of the spreader.The results show that the improved jellyfish algorithm can efficiently and accurately find out the optimal shape and weight of the spreader,and throughMidas Civil simulation,the spreader used canmeet the requirements of weight and safety.展开更多
To realize high-value utilization of discarded apple peel,this study investigated the effects of three selected commercial drying methods on drying kinetics,microstructure,color,phenolic stability and antioxidant capa...To realize high-value utilization of discarded apple peel,this study investigated the effects of three selected commercial drying methods on drying kinetics,microstructure,color,phenolic stability and antioxidant capacity of apple peel.Apple peel was dehydrated by hot air drying(AD)at 75,65 and 55℃,heat pump drying(HP)at 65,55 and 45℃,and vacuum freeze-drying(FD),respectively.The results showed that HP was superior to AD and FD in terms of drying rate.In addition,HP at 65℃provided high-quality dried apple peel due to less browning and brighter appearance,the highest retention of total phenolics(29.35 mg/g)and the strongest antioxidant activities,with the highest ABTS and FRAP value of 127.15 and 219.57μmol TE/g,respectively.The content of the six major individual phenolics,i.e.caffeic acid,(-)-epicatechin,hyperoside,rutin,phlorizin and quercitrin,were found to be the highest in HP dried samples.Interestingly,the content of rutin was even increased after HP compared to the fresh sample.Considering drying efficiency,organoleptic quality and phenolic stability of the products,HP at 65°C is suggested for drying of apple peel.展开更多
This paper proposes the operation principle and a new flux estimation method for sensorless control strategy for the dual-fed flux modulated electric motor(DFFM).The DFFM is designed based on the flux modulation theor...This paper proposes the operation principle and a new flux estimation method for sensorless control strategy for the dual-fed flux modulated electric motor(DFFM).The DFFM is designed based on the flux modulation theory,it includes two stator windings and one rotor which simplify the mechanical structure.The rotor has only modulation iron and no permanent magnets on it,so there is no cogging torque problem in this motor.With adjustment of the outer and inner stator flux rotating frequency and amplitude,different rotation speed and torque of the sandwiched rotor can be gained for the DFFM.Furthermore,an improved flux estimation based sensorless control strategy is performed on the proposed machine to fit the two winding set control situation.The startup and performance of the proposed control strategy is verified by the simulation and experiments.展开更多
Individuals with autism spectrum disorder(ASD)often exhibit motor deficits that increase their risk of falls.There is a lack of understanding regarding gait biomechanics demonstrated by older children with ASD.The pur...Individuals with autism spectrum disorder(ASD)often exhibit motor deficits that increase their risk of falls.There is a lack of understanding regarding gait biomechanics demonstrated by older children with ASD.The purpose of the study was to determine differences in gait patterns between older children with ASD and typically developing children.Eleven children with ASD and 11 age-and gender-matched typically developing children were recruited for the study.Participants walked on a force-instrumented treadmill at a constant speed(1.1 m/s-1.2 m/s)for five minutes(min).Participants performed maximal voluntary contractions to assess their knee muscular strength.Differences between individuals with ASD and matched control participants were examined through paired t-tests with a significance level of p0.05.Individuals with ASD demonstrated a smaller knee extensor torque compared to controls(p=0.002).Participants with ASD exhibited a shorter stride length(p=0.04),a greater cadence(p=0.03),and a higher variation in stride width(p=0.04)compared to control participants.The individuals with ASD experienced a greater braking ground reaction force(p=0.03)during loading response.The results indicate older children with ASD develop a unique gait pattern signified by a reduced stride length,increased cadence,and an increase of variation in stride width.This unique gait pattern may represent a movement strategy used by the individuals with ASD to compensate for the weakness associated with their knee extensor muscles.Individuals with ASD who demonstrate these unique gait deviations may face reduced postural stability and an increased risk of fall-related injuries.展开更多
基金the National Natural Science Foundation of China(Grant No.51305372)the Open Fund Project of the Transportation Infrastructure Intelligent Management and Maintenance Engineering Technology Center of Xiamen City(Grant No.TCIMI201803)the Project of the 2011 Collaborative Innovation Center of Fujian Province(Grant No.2016BJC019).
文摘In this paper,given the shortcomings of jellyfish search algorithmwith low search ability in the early stage and easy to fall into local optimal solution,this paper introduces adaptive weight function and elite strategy,improving the global search scope in the early stage and the ability to refine the local development in the later stage.In the numerical study,the benchmark problem of dimensional optimization with a 10-bar truss structure and simultaneous dimensional shape optimization with a 15-bar truss structure is adopted,and the corresponding penalty method is used for constraint treatment.The test results show that the improved jellyfish search algorithm can provide better truss sections as well as weights.Because when the steel main truss of the large-span covered bridge is lifted,the site is limited and the large lifting equipment cannot enter the site,and the original structure does not meet the problem of stress concentration and large deformation of the bolt group,so the spreader is used to lift,and the improved jellyfish search algorithm is introduced into the design optimization of the spreader.The results show that the improved jellyfish algorithm can efficiently and accurately find out the optimal shape and weight of the spreader,and throughMidas Civil simulation,the spreader used canmeet the requirements of weight and safety.
基金the National Key R&D Program of China(2016YFD0400700,2016YFD0400704)the Central Public-interest Scientific Institution Basal Research Fund(No.S2019RCCG01).
文摘To realize high-value utilization of discarded apple peel,this study investigated the effects of three selected commercial drying methods on drying kinetics,microstructure,color,phenolic stability and antioxidant capacity of apple peel.Apple peel was dehydrated by hot air drying(AD)at 75,65 and 55℃,heat pump drying(HP)at 65,55 and 45℃,and vacuum freeze-drying(FD),respectively.The results showed that HP was superior to AD and FD in terms of drying rate.In addition,HP at 65℃provided high-quality dried apple peel due to less browning and brighter appearance,the highest retention of total phenolics(29.35 mg/g)and the strongest antioxidant activities,with the highest ABTS and FRAP value of 127.15 and 219.57μmol TE/g,respectively.The content of the six major individual phenolics,i.e.caffeic acid,(-)-epicatechin,hyperoside,rutin,phlorizin and quercitrin,were found to be the highest in HP dried samples.Interestingly,the content of rutin was even increased after HP compared to the fresh sample.Considering drying efficiency,organoleptic quality and phenolic stability of the products,HP at 65°C is suggested for drying of apple peel.
文摘This paper proposes the operation principle and a new flux estimation method for sensorless control strategy for the dual-fed flux modulated electric motor(DFFM).The DFFM is designed based on the flux modulation theory,it includes two stator windings and one rotor which simplify the mechanical structure.The rotor has only modulation iron and no permanent magnets on it,so there is no cogging torque problem in this motor.With adjustment of the outer and inner stator flux rotating frequency and amplitude,different rotation speed and torque of the sandwiched rotor can be gained for the DFFM.Furthermore,an improved flux estimation based sensorless control strategy is performed on the proposed machine to fit the two winding set control situation.The startup and performance of the proposed control strategy is verified by the simulation and experiments.
文摘Individuals with autism spectrum disorder(ASD)often exhibit motor deficits that increase their risk of falls.There is a lack of understanding regarding gait biomechanics demonstrated by older children with ASD.The purpose of the study was to determine differences in gait patterns between older children with ASD and typically developing children.Eleven children with ASD and 11 age-and gender-matched typically developing children were recruited for the study.Participants walked on a force-instrumented treadmill at a constant speed(1.1 m/s-1.2 m/s)for five minutes(min).Participants performed maximal voluntary contractions to assess their knee muscular strength.Differences between individuals with ASD and matched control participants were examined through paired t-tests with a significance level of p0.05.Individuals with ASD demonstrated a smaller knee extensor torque compared to controls(p=0.002).Participants with ASD exhibited a shorter stride length(p=0.04),a greater cadence(p=0.03),and a higher variation in stride width(p=0.04)compared to control participants.The individuals with ASD experienced a greater braking ground reaction force(p=0.03)during loading response.The results indicate older children with ASD develop a unique gait pattern signified by a reduced stride length,increased cadence,and an increase of variation in stride width.This unique gait pattern may represent a movement strategy used by the individuals with ASD to compensate for the weakness associated with their knee extensor muscles.Individuals with ASD who demonstrate these unique gait deviations may face reduced postural stability and an increased risk of fall-related injuries.