ZnO nanocrystals were prepared by a direct current electrochemical deposition process under 3.0V working voltage and 30A/m^2 current density using zinc sulfate as raw materials.The nanocrystals were characterized by X...ZnO nanocrystals were prepared by a direct current electrochemical deposition process under 3.0V working voltage and 30A/m^2 current density using zinc sulfate as raw materials.The nanocrystals were characterized by X-ray diffraction (XRD)and transmission electron microscopy(TEM).The results indicated that the nanocrystals are hexagonal wurtzite ZnO with particle size range of 25nm～40nm without any treating.Gas sensing properties of the sensors were tested by mixing a gas in air at static state;the tested results showed that the sensors based on nanocrystalline ZnO had satisfied gas sensing properties to H_2S gas at rather low temperature.展开更多
In this paper, a new reliable H-infinity filter design problem is proposed for a class of continuous-time sys- tems with sensor saturation and failures. Attention is focused on the analysis and synthesis problems of a...In this paper, a new reliable H-infinity filter design problem is proposed for a class of continuous-time sys- tems with sensor saturation and failures. Attention is focused on the analysis and synthesis problems of a full order reliable H-infinity filter such that the filtering error dynamics is asymptotically stable with a guaranteed disturbance rejection atten- uation level -y. It is shown that the filtering error dynamics obtained from the original system plus the filter can be modeled by a linear system with sector bounded nonlinearity. The design conditions are given in terms of solutions to a set of linear matrix inequalities （LMIs）. These conditions are then considered in a convex optimization problem with LMIs constraints in order to design an optimal reliable H-infinity filter. A numerical example is given to illustrate the effectiveness of the proposed results.展开更多
基金Supported by National Basic Research Program of China （973 Program） （2010CB731800） and National Natural Science Foundation of China （60974059, 60736026, 61021063）
文摘ZnO nanocrystals were prepared by a direct current electrochemical deposition process under 3.0V working voltage and 30A/m^2 current density using zinc sulfate as raw materials.The nanocrystals were characterized by X-ray diffraction (XRD)and transmission electron microscopy(TEM).The results indicated that the nanocrystals are hexagonal wurtzite ZnO with particle size range of 25nm～40nm without any treating.Gas sensing properties of the sensors were tested by mixing a gas in air at static state;the tested results showed that the sensors based on nanocrystalline ZnO had satisfied gas sensing properties to H_2S gas at rather low temperature.
基金supported by the National Creative Research Groups Science Foundation of China (No. 60721062)the Foundation of Zhejiang Department of Education (No. Y201121463)National Natural Science Foundation of China (Nos. 61203025, 60974138)
文摘In this paper, a new reliable H-infinity filter design problem is proposed for a class of continuous-time sys- tems with sensor saturation and failures. Attention is focused on the analysis and synthesis problems of a full order reliable H-infinity filter such that the filtering error dynamics is asymptotically stable with a guaranteed disturbance rejection atten- uation level -y. It is shown that the filtering error dynamics obtained from the original system plus the filter can be modeled by a linear system with sector bounded nonlinearity. The design conditions are given in terms of solutions to a set of linear matrix inequalities （LMIs）. These conditions are then considered in a convex optimization problem with LMIs constraints in order to design an optimal reliable H-infinity filter. A numerical example is given to illustrate the effectiveness of the proposed results.
