In this paper,a stable and adaptive sliding mode control(SMC)method for induction motors is introduced.Determining the parameters of this system has been one of the existing challenges.To solve this challenge,a new se...In this paper,a stable and adaptive sliding mode control(SMC)method for induction motors is introduced.Determining the parameters of this system has been one of the existing challenges.To solve this challenge,a new self-tuning type-2 fuzzy neural network calculates and updates the control system parameters with a fast mechanism.According to the dynamic changes of the system,in addition to the parameters of the SMC,the parameters of the type-2 fuzzy neural network are also updated online.The conditions for guaranteeing the convergence and stability of the control system are provided.In the simulation part,in order to test the proposed method,several uncertain models and load torque have been applied.Also,the results have been compared to the SMC based on the type-1 fuzzy system,the traditional SMC,and the PI controller.The average RMSE in different scenarios,for type-2 fuzzy SMC,is 0.0311,for type-1 fuzzy SMC is 0.0497,for traditional SMC is 0.0778,and finally for PI controller is 0.0997.展开更多
In the era of accelerated development in artificial intelligence as well as explosive growth of information and data throughput,underlying hardware devices that can integrate perception and memory while simultaneously...In the era of accelerated development in artificial intelligence as well as explosive growth of information and data throughput,underlying hardware devices that can integrate perception and memory while simultaneously offering the bene-fits of low power consumption and high transmission rates are particularly valuable.Neuromorphic devices inspired by the human brain are considered to be one of the most promising successors to the efficient in-sensory process.In this paper,a homojunction-based multi-functional optoelectronic synapse(MFOS)is proposed and testified.It enables a series of basic electri-cal synaptic plasticity,including paired-pulse facilitation/depression(PPF/PPD)and long-term promotion/depression(LTP/LTD).In addition,the synaptic behaviors induced by electrical signals could be instead achieved through optical signals,where its sen-sitivity to optical frequency allows the MFOS to simulate high-pass filtering applications in situ and the perception capability integrated into memory endows it with the information acquisition and processing functions as a visual system.Meanwhile,the MFOS exhibits its performances of associative learning and logic gates following the illumination with two different wave-lengths.As a result,the proposed MFOS offers a solution for the realization of intelligent visual system and bionic electronic eye,and will provide more diverse application scenarios for future neuromorphic computing.展开更多
The primary purpose of this research is to improve the seismic response of a complex asymmetric tall structure using viscoelastic(VE) dampers. Asymmetric structures have detrimental effects on the seismic performance ...The primary purpose of this research is to improve the seismic response of a complex asymmetric tall structure using viscoelastic(VE) dampers. Asymmetric structures have detrimental effects on the seismic performance because such structures create abrupt changes in the stiffness or strength that may lead to undesirable stress concentrations at weak locations. Structural control devices are one of the effective ways to reduce seismic impacts, particularly in asymmetric structures. For passive vibration control of structures, VE dampers are considered among the most preferred devices for energy dissipation. Therefore, in this research, VE dampers are implemented at strategic locations in a realistic case study structure to increase the level of distributed damping without occupying significant architectural space and reducing earthquake vibrations in terms of story displacements(drifts) and other design forces. It has been concluded that the seismic response of the considered structure retrofitted with supplemental VE dampers corresponded well in controlling the displacement demands. Moreover, it has been demonstrated that seismic response in terms of interstory drifts was effectively mitigated with supplemental damping when added up to a certain level. Exceeding the supplemental damping from this level did not contribute to additional mitigation of the seismic response of the considered structure. In addition, it was found that the supplemental damping increased the total acceleration of the considered structure at all floor levels, which indicates that for irregular tall structures of this type, VE dampers were only a good retrofitting measure for earthquake induced interstory deformations and their use may not be suitable for acceleration sensitive structures. Overall, the research findings demonstrate how seismic hazards to these types of structures can be reduced by introducing additional damping into the structure.展开更多
Developing a cotton fabric sensing layer with good waterproofness and breathability via a low-cost and eco-friendly method is increasingly important for the construction of comfortable and wearable electronic devices....Developing a cotton fabric sensing layer with good waterproofness and breathability via a low-cost and eco-friendly method is increasingly important for the construction of comfortable and wearable electronic devices.Herein,a waterproof and breathable cotton fabric composite decorated by reduced graphene oxide(rGO)and carbon nanotube(CNT),Cotton/rGO/CNT,is reported by a facile solution infiltration method,and we adopt such Cotton/rGO/CNT composite to develop a layer-by-layer structured multifunctional flexible sensor,enabling the high-sensitivity detection of pressure and temperature stimulus.Particularly,the multifunctional flexible sensor exhibits a high response toward tiny pressure,demonstrating salient superiority in the continuous and reliable monitoring of human physiological information.Concerning temperature sensing,a good linear response for the temperatures ranging from 28 to 40℃ is achieved by the multifunctional flexible sensor and gives rise to be successfully applied to the non-contact real-time monitoring of human respiration signal.Finally,an array consisting of multifunctional flexible sensors further demonstrates its feasibility in perceiving and mapping the pressure and temperature information of contact objects.This work provides a feasible strategy for designing cotton-based sensing layers that can effectively resist liquid water penetration and allow water vapor transmission,and offers reasonable insight for constructing comfort and multifunctional wearable electronics.展开更多
Interfacial thermal conductance plays a sig- nificant role in the heat transfer efficiency of nanoscale systems. The thermal conductance across Al/SiO_2 inter- faces, which is subjected to the change in concentration ...Interfacial thermal conductance plays a sig- nificant role in the heat transfer efficiency of nanoscale systems. The thermal conductance across Al/SiO_2 inter- faces, which is subjected to the change in concentration of sandwiched Rhodamine 6G solution, is measured with time domain transient thermoreflectance technique. The thermal conductance of the interface between Al and SiO_2 logarithmically decreases with an increase in the concen- tration of the Rhodamine 6G solution. This study reveals that heat transport efficiency across an interface can be conveniently manipulated according to the demand of thermal engineering by introducing organic moleculars between both sides of the interface.展开更多
Reinforced concretes(RC)have been widely used in constructions.In construction,one of the eritical elements carrying a high percentage of the weight is columns which were not used 1o design to absorb large dynamic loa...Reinforced concretes(RC)have been widely used in constructions.In construction,one of the eritical elements carrying a high percentage of the weight is columns which were not used 1o design to absorb large dynamic load like surface bursts.This study focuses on investigating blast load parameters to design of RC columns to withstand blast detonation.The numerical model is based on finite element amalysis using LS-DYNA.Numerical results are validated against blast feld tests available in the lterature.Couples of simulations are performed with changing blast parameters to.study efects of various scaled distances on the nonlinear bchavior of RC columns.According to simulation results,the scaled distance has a substantial infuence on the blast response of RC columns.With lower scaled distance,higher peak pressure and larger pressure impulse are applied on the RC column.Eventually,keeping the scaled disance unchanged,increasing the charge weight or shorter standoff distance cause more damage to the RC column.Intensive studies are carried out to investigate the efects of scaled distance and charge weight on the damage degree and residual axial load carrying capacity of RC columns with various column width,longitudinal reinforcement ratio and concrete strength.Results of this research will be used to asessmsent the efet of an explosion on the dynamic behavior of RC columns.展开更多
Incineration experiment of medical waste was carried out in a mobile animal carcass incinerator.Simulated medical waste(69%cotton,1.5%wood product,4.5%mask and 25%moisture)was used as raw material.The temperature tren...Incineration experiment of medical waste was carried out in a mobile animal carcass incinerator.Simulated medical waste(69%cotton,1.5%wood product,4.5%mask and 25%moisture)was used as raw material.The temperature trend of first and second combustion chamber,the operating conditions and the emission characteristics of gaseous pollutants were studied.The results indicated that the temperature of first combustion chamber can be maintained at 550-650℃ without external heating,while in the final stage a burner was used to realize the burnout of material.The temperature of the second combustion chamber was always lower than that of the first combustion after the burner stopped working.The concentration of CO emission in flue gas was high due to the low disposal efficiency of the mobile incinerator,while NOX and SO2 emission concentrations were far below the standard limit value(GB 18484-2001).展开更多
基金This research is financially supported by the Ministry of Science and Technology of China(Grant No.2019YFE0112400)the Department of Science and Technology of Shandong Province(Grant No.2021CXGC011204).
文摘In this paper,a stable and adaptive sliding mode control(SMC)method for induction motors is introduced.Determining the parameters of this system has been one of the existing challenges.To solve this challenge,a new self-tuning type-2 fuzzy neural network calculates and updates the control system parameters with a fast mechanism.According to the dynamic changes of the system,in addition to the parameters of the SMC,the parameters of the type-2 fuzzy neural network are also updated online.The conditions for guaranteeing the convergence and stability of the control system are provided.In the simulation part,in order to test the proposed method,several uncertain models and load torque have been applied.Also,the results have been compared to the SMC based on the type-1 fuzzy system,the traditional SMC,and the PI controller.The average RMSE in different scenarios,for type-2 fuzzy SMC,is 0.0311,for type-1 fuzzy SMC is 0.0497,for traditional SMC is 0.0778,and finally for PI controller is 0.0997.
基金supported by the National Natural Science Foundation of China under Grant(62174068,61625404).
文摘In the era of accelerated development in artificial intelligence as well as explosive growth of information and data throughput,underlying hardware devices that can integrate perception and memory while simultaneously offering the bene-fits of low power consumption and high transmission rates are particularly valuable.Neuromorphic devices inspired by the human brain are considered to be one of the most promising successors to the efficient in-sensory process.In this paper,a homojunction-based multi-functional optoelectronic synapse(MFOS)is proposed and testified.It enables a series of basic electri-cal synaptic plasticity,including paired-pulse facilitation/depression(PPF/PPD)and long-term promotion/depression(LTP/LTD).In addition,the synaptic behaviors induced by electrical signals could be instead achieved through optical signals,where its sen-sitivity to optical frequency allows the MFOS to simulate high-pass filtering applications in situ and the perception capability integrated into memory endows it with the information acquisition and processing functions as a visual system.Meanwhile,the MFOS exhibits its performances of associative learning and logic gates following the illumination with two different wave-lengths.As a result,the proposed MFOS offers a solution for the realization of intelligent visual system and bionic electronic eye,and will provide more diverse application scenarios for future neuromorphic computing.
基金Supported by:Ministry of Science and Technology of China under Grant No.2017YFC0703603National Natural Science Foundation of China under Grant No.51678322
文摘The primary purpose of this research is to improve the seismic response of a complex asymmetric tall structure using viscoelastic(VE) dampers. Asymmetric structures have detrimental effects on the seismic performance because such structures create abrupt changes in the stiffness or strength that may lead to undesirable stress concentrations at weak locations. Structural control devices are one of the effective ways to reduce seismic impacts, particularly in asymmetric structures. For passive vibration control of structures, VE dampers are considered among the most preferred devices for energy dissipation. Therefore, in this research, VE dampers are implemented at strategic locations in a realistic case study structure to increase the level of distributed damping without occupying significant architectural space and reducing earthquake vibrations in terms of story displacements(drifts) and other design forces. It has been concluded that the seismic response of the considered structure retrofitted with supplemental VE dampers corresponded well in controlling the displacement demands. Moreover, it has been demonstrated that seismic response in terms of interstory drifts was effectively mitigated with supplemental damping when added up to a certain level. Exceeding the supplemental damping from this level did not contribute to additional mitigation of the seismic response of the considered structure. In addition, it was found that the supplemental damping increased the total acceleration of the considered structure at all floor levels, which indicates that for irregular tall structures of this type, VE dampers were only a good retrofitting measure for earthquake induced interstory deformations and their use may not be suitable for acceleration sensitive structures. Overall, the research findings demonstrate how seismic hazards to these types of structures can be reduced by introducing additional damping into the structure.
基金supported by the National Natural Science Foundation of China(Nos.62174068,61805101,62005095,61888102,and 62104080)Shandong Provincial Natural Science Foundation of China(Nos.ZR2019BF013 and ZR2020QF105)Rizhao City Key Research and Development Program under Grant(No.2021ZDYF010102).
文摘Developing a cotton fabric sensing layer with good waterproofness and breathability via a low-cost and eco-friendly method is increasingly important for the construction of comfortable and wearable electronic devices.Herein,a waterproof and breathable cotton fabric composite decorated by reduced graphene oxide(rGO)and carbon nanotube(CNT),Cotton/rGO/CNT,is reported by a facile solution infiltration method,and we adopt such Cotton/rGO/CNT composite to develop a layer-by-layer structured multifunctional flexible sensor,enabling the high-sensitivity detection of pressure and temperature stimulus.Particularly,the multifunctional flexible sensor exhibits a high response toward tiny pressure,demonstrating salient superiority in the continuous and reliable monitoring of human physiological information.Concerning temperature sensing,a good linear response for the temperatures ranging from 28 to 40℃ is achieved by the multifunctional flexible sensor and gives rise to be successfully applied to the non-contact real-time monitoring of human respiration signal.Finally,an array consisting of multifunctional flexible sensors further demonstrates its feasibility in perceiving and mapping the pressure and temperature information of contact objects.This work provides a feasible strategy for designing cotton-based sensing layers that can effectively resist liquid water penetration and allow water vapor transmission,and offers reasonable insight for constructing comfort and multifunctional wearable electronics.
基金This work was supported by the National Basic Research Program of China (2011CB707605), the National Natural Science Foundation of China (51205061 and 51405418). Natural Science Foundation of Jiangsu Province (BK2012340), the Ph.D. Programs Foundation of Ministry of Education of China (20110092120006), and Six Talent Peaks Project of Jiangsu Province (2013-ZBZZ-026).
文摘Interfacial thermal conductance plays a sig- nificant role in the heat transfer efficiency of nanoscale systems. The thermal conductance across Al/SiO_2 inter- faces, which is subjected to the change in concentration of sandwiched Rhodamine 6G solution, is measured with time domain transient thermoreflectance technique. The thermal conductance of the interface between Al and SiO_2 logarithmically decreases with an increase in the concen- tration of the Rhodamine 6G solution. This study reveals that heat transport efficiency across an interface can be conveniently manipulated according to the demand of thermal engineering by introducing organic moleculars between both sides of the interface.
基金The research was financially supported by the Ministry of Science and Technology of China(No.2017YFC0703603)the Taishan Scholar Priority Discipline Talent Group program funded by the Shandong Province,and the Universiti Kebangsaan Malaysia Grant FRGS-1-2015-TK01-UKM02-4 and AP-2015-011.
文摘Reinforced concretes(RC)have been widely used in constructions.In construction,one of the eritical elements carrying a high percentage of the weight is columns which were not used 1o design to absorb large dynamic load like surface bursts.This study focuses on investigating blast load parameters to design of RC columns to withstand blast detonation.The numerical model is based on finite element amalysis using LS-DYNA.Numerical results are validated against blast feld tests available in the lterature.Couples of simulations are performed with changing blast parameters to.study efects of various scaled distances on the nonlinear bchavior of RC columns.According to simulation results,the scaled distance has a substantial infuence on the blast response of RC columns.With lower scaled distance,higher peak pressure and larger pressure impulse are applied on the RC column.Eventually,keeping the scaled disance unchanged,increasing the charge weight or shorter standoff distance cause more damage to the RC column.Intensive studies are carried out to investigate the efects of scaled distance and charge weight on the damage degree and residual axial load carrying capacity of RC columns with various column width,longitudinal reinforcement ratio and concrete strength.Results of this research will be used to asessmsent the efet of an explosion on the dynamic behavior of RC columns.
文摘Incineration experiment of medical waste was carried out in a mobile animal carcass incinerator.Simulated medical waste(69%cotton,1.5%wood product,4.5%mask and 25%moisture)was used as raw material.The temperature trend of first and second combustion chamber,the operating conditions and the emission characteristics of gaseous pollutants were studied.The results indicated that the temperature of first combustion chamber can be maintained at 550-650℃ without external heating,while in the final stage a burner was used to realize the burnout of material.The temperature of the second combustion chamber was always lower than that of the first combustion after the burner stopped working.The concentration of CO emission in flue gas was high due to the low disposal efficiency of the mobile incinerator,while NOX and SO2 emission concentrations were far below the standard limit value(GB 18484-2001).