By expressing the wave functions in the form of Fourier-Bessel series, the analytical solution for the two-dimension scattering problem of plane P waves by the cylindrical canyon topography that contains arbitrary num...By expressing the wave functions in the form of Fourier-Bessel series, the analytical solution for the two-dimension scattering problem of plane P waves by the cylindrical canyon topography that contains arbitrary number of circular-arc-shaped layers is presented firstly. And then, the convergence of the proposed series solution with the truncation number of terms is discussed, which demonstrates that the analytical solution can converge even for very high frequencies of the incident P wave. Finally, using this solution, the influences that are imposed on the stationary ground motion by the number and the sequence of alluvial layers, as well as the stiffness of soft interlayer contained in the canyon, are studied,展开更多
A field monitoring program was carried out to record the slope failure process of a landfill with multiple intermediate covering layers.The monitored items include the leachate level,the surface horizontal displacemen...A field monitoring program was carried out to record the slope failure process of a landfill with multiple intermediate covering layers.The monitored items include the leachate level,the surface horizontal displacement and the deep lateral displacement.Based on the monitoring data,analysis was carried out to verify the stability control effects of leachate drainage on the top layer,leachate drainage in different layers,and near-slope leachate drainage.The results show that the maximum slip area is 34 760 m 2 and the average surface horizontal displacement of the 10th platform is 1.77 m.Dumping near the slope is the main reason for the instability.The closer to the dumping area,the greater the degree of slip and the more significantly the leachate level rises.Affected by the intermediate covering layers,the failure mode is the local sliding inside the landfill,and the effect of near-slope leachate drainage on the stability control is obvious.展开更多
We report field measurements of vertical profiles of the turbulent diffusivity and temperature at different stations in the South China Sea(SCS).Our study shows that the measured turbulent diffusivity follows a power-...We report field measurements of vertical profiles of the turbulent diffusivity and temperature at different stations in the South China Sea(SCS).Our study shows that the measured turbulent diffusivity follows a power-law distribution with a varying exponent in water layers.Similar multiple-layer scaling regimes were also observed from the temperature fluctuations.Combining turbulent diffusivity and temperature fluctuations,the vertical structure of temperature was revealed.Furthermore,we discussed the temperature profiles in each layer.A constant function of a dimensionless temperature profile was found in water layers that have identical turbulence conditions.Our results reveal the multiple-layer structure of temperature in the SCS.This study contributes to the understanding of the vertical structure of multiple layers in the SCS and provides clues for exploring the physical mechanism for maintaining the temperature structure.展开更多
Natural frequency characteristics of a thin-walled multiple layered cylindrical shell under lateral pressure are studied. The multiple layered cylindrical shell configuration is formed by three layers of isotropic mat...Natural frequency characteristics of a thin-walled multiple layered cylindrical shell under lateral pressure are studied. The multiple layered cylindrical shell configuration is formed by three layers of isotropic material where the inner and outer layers are stainless steel and the middle layer is aluminum. The multiple layered shell equations with lateral pressure are established based on Love's shell theory. The governing equations of motion with lateral pressure are employed by using energy functional and applying the Ritz method. The boundary conditions represented by end conditions of the multiple layered cylindrical shell are simply supported-clamped(SS-C), free-clamped(F-C) and simply supported-free(SS-F). The influence of different lateral pressures, different thickness to radius ratios, different length to radius ratios and effect of the asymmetric boundary conditions on natural frequency characteristics are studied. It is shown that the lateral pressure has effect on the natural frequency of multiple layered cylindrical shell and causes the natural frequency to increase. The natural frequency of the developed multilayered cylindrical shell is validated by comparing with those in the literature. The proposed research provides an effective approach for vibration analysis shell structures subjected to lateral pressure with an energy method.展开更多
A series of white phosphorescent OLED devices with buffer layer and multiple dopant structure is investigated in order to obtain better electro-optic performances and color stability. The color coordinate and color st...A series of white phosphorescent OLED devices with buffer layer and multiple dopant structure is investigated in order to obtain better electro-optic performances and color stability. The color coordinate and color stability are related to the location of multiple dopants layer, and the optimized location can compensate for the change of the blue emission intensity under a high voltage and stabilize the spectrum. The electro-optic performances and color stability can be further improved by changing the composition and thickness of the buffer layer between the emitting layer and the electron transport layer.In device B2, the distance from multiple dopant layer to buffer layer is 2 nm and the thickness of buffer layer is 5 nm,the maximum luminance, current density, and power efficiency can reach 9091 cd/m^2, 364.5 mA/cm^2, and 26.74 lm/W,respectively. The variation of international commission on the illumination(CIE) coordinate of device B2 with voltage increasing from 4 V to 7 V is only(0.006, 0.004).展开更多
In this paper, we reveal the multiple boundary layer phenomena of the solution of nonlinear higher order elliptic equations with perturbation both in boundary and in operator, and provide a method to find uniformly va...In this paper, we reveal the multiple boundary layer phenomena of the solution of nonlinear higher order elliptic equations with perturbation both in boundary and in operator, and provide a method to find uniformly valid asymptotic solution of arbitrary order for these types of problems.展开更多
The method of boundary layer with multiple scales and computer algebra were applied to study the asymptotic behavior of solution of boundary value problems for a class of system of nonlinear differential equations . T...The method of boundary layer with multiple scales and computer algebra were applied to study the asymptotic behavior of solution of boundary value problems for a class of system of nonlinear differential equations . The asymptotic expansions of solution were constructed. The remainders were estimated. And an example was analysed. It provides a new foreground for the application of the method of boundary layer with multiple scales .展开更多
Dear Sir,Ifound the article by Sobac1etal[1]very interesting.The authors concluded that repeated intravitreal injection(IVI)of ranibizumab or bevacizumab didn’t seem have adverse effects on retinal nerve fiber layer(...Dear Sir,Ifound the article by Sobac1etal[1]very interesting.The authors concluded that repeated intravitreal injection(IVI)of ranibizumab or bevacizumab didn’t seem have adverse effects on retinal nerve fiber layer(RNFL)thickness in wet age-related macular degeneration(AMD)patients.展开更多
The multiple absorber layer perovskite solar cells(PSCs)with charge transport layers-free(CTLs-free)have drawn widespread research interest due to their simplified architecture and promising photoelectric characterist...The multiple absorber layer perovskite solar cells(PSCs)with charge transport layers-free(CTLs-free)have drawn widespread research interest due to their simplified architecture and promising photoelectric characteristics.Under the circumstances,the novel design of CTLs-free inversion PSCs with stable and nontoxic three absorber layers(triple Cs_(3)Bi_(2)I_(9),single MASnI_(3),double Cs_(2)TiBr_(6))as optical-harvester has been numerically simulated by utilizing wxAMPS simulation software and achieved high power conversion efficiency(PCE)of 14.8834%.This is owing to the innovative architecture of PSCs favors efficient transport and extraction of more holes and the slender band gap MASnI_(3)extends the absorption spectrum to the near-infrared periphery compared with the two absorber layers architecture of PSCs.Moreover,the performance of the device with p-type-Cs_(3)Bi_(2)I_(9)/p-type-MASnI_(3)/n-type-Cs_(2)TiBr_(6)architecture is superior to the one with the p-type-Cs_(3)Bi_(2)I_(9)/ntype-MASnI_(3)/n-type-Cs_(2)TiBr_(6)architecture due to less carrier recombination and higher carrier life time inside the absorber layers.The simulation results reveal that Cs_(2)TiF_(6)double perovskite material stands out as the best alternative.Additionally,an excellent PCE of 21.4530%can be obtained with the thicker MASnI_(3)absorber layer thickness(0.4μm).Lastly,the highestperformance photovoltaic devices(28.6193%)can be created with the optimized perovskite doping density of around E15 cm^(3)(Cs_(3)Bi_(2)I_(9)),E18 cm^(3)(MASnI_(3)),and 1.5E19 cm^(3)(Cs_(2)TiBr_(6)).This work manifests that the proposed CTLs-free PSCs with multi-absorber layers shall be a relevant reference for forward applications in electro-optical and optoelectronic devices.展开更多
In this paper, we study the multiple boundary layer phenomena of solution ofboundary value problem for third order semilinear ordinary differential equationwith two small parameters. Under suitable conditions, using t...In this paper, we study the multiple boundary layer phenomena of solution ofboundary value problem for third order semilinear ordinary differential equationwith two small parameters. Under suitable conditions, using the method of differential inequalities, we prove the existence of solution and give its estimation of remmainder term.展开更多
In this paper, we study the singular perturbation of boundary value problem for a class of n-th order nonlinear differential equation, the solution is shown to exhibit multiple layer behavior. According to different l...In this paper, we study the singular perturbation of boundary value problem for a class of n-th order nonlinear differential equation, the solution is shown to exhibit multiple layer behavior. According to different layers and by introducing extended variable, we obtain the uniformly effective asymptotic expansion with different boundary layer correction term.展开更多
Service recommendation provides an effective solution to extract valuable information from the huge and ever-increasing volume of big data generated by the large cardinality of user devices.However,the distributed and...Service recommendation provides an effective solution to extract valuable information from the huge and ever-increasing volume of big data generated by the large cardinality of user devices.However,the distributed and rich multi-source big data resources raise challenges to the centralized cloud-based data storage and value mining approaches in terms of economic cost and effective service recommendation methods.In view of these challenges,we propose a deep neural collaborative filtering based service recommendation method with multi-source data(i.e.,NCF-MS)in this paper,which adopts the cloud-edge collaboration computing paradigm to build recommendation model.More specifically,the Stacked Denoising Auto Encoder(SDAE)module is adopted to extract user/service features from auxiliary user profiles and service attributes.The Multiple Layer Perceptron(MLP)module is adopted to integrate the auxiliary user/service features to train the recommendation model.Finally,we evaluate the effectiveness of the NCF-MS method on three public datasets.The experimental results show that our proposed method achieves better performance than existing methods.展开更多
Motivated by the autopilot of an unmanned aerial vehicle(UAV) with a wide flight envelope span experiencing large parametric variations in the presence of uncertainties, a fuzzy adaptive tracking controller(FATC) ...Motivated by the autopilot of an unmanned aerial vehicle(UAV) with a wide flight envelope span experiencing large parametric variations in the presence of uncertainties, a fuzzy adaptive tracking controller(FATC) is proposed. The controller consists of a fuzzy baseline controller and an adaptive increment, and the main highlight is that the fuzzy baseline controller and adaptation laws are both based on the fuzzy multiple Lyapunov function approach, which helps to reduce the conservatism for the large envelope and guarantees satisfactory tracking performances with strong robustness simultaneously within the whole envelope. The constraint condition of the fuzzy baseline controller is provided in the form of linear matrix inequality(LMI), and it specifies the satisfactory tracking performances in the absence of uncertainties. The adaptive increment ensures the uniformly ultimately bounded(UUB) predication errors to recover satisfactory responses in the presence of uncertainties. Simulation results show that the proposed controller helps to achieve high-accuracy tracking of airspeed and altitude desirable commands with strong robustness to uncertainties throughout the entire flight envelope.展开更多
基金supported by the National Natural Science Foundation of China under grant No.50608066Chinese Earthquake Science Foundation under grant No.A07045
文摘By expressing the wave functions in the form of Fourier-Bessel series, the analytical solution for the two-dimension scattering problem of plane P waves by the cylindrical canyon topography that contains arbitrary number of circular-arc-shaped layers is presented firstly. And then, the convergence of the proposed series solution with the truncation number of terms is discussed, which demonstrates that the analytical solution can converge even for very high frequencies of the incident P wave. Finally, using this solution, the influences that are imposed on the stationary ground motion by the number and the sequence of alluvial layers, as well as the stiffness of soft interlayer contained in the canyon, are studied,
基金The National Basic Research Program of China(973Project)(No.2012CB719800)the National Natural Science Foundation of China(No.41502276)
文摘A field monitoring program was carried out to record the slope failure process of a landfill with multiple intermediate covering layers.The monitored items include the leachate level,the surface horizontal displacement and the deep lateral displacement.Based on the monitoring data,analysis was carried out to verify the stability control effects of leachate drainage on the top layer,leachate drainage in different layers,and near-slope leachate drainage.The results show that the maximum slip area is 34 760 m 2 and the average surface horizontal displacement of the 10th platform is 1.77 m.Dumping near the slope is the main reason for the instability.The closer to the dumping area,the greater the degree of slip and the more significantly the leachate level rises.Affected by the intermediate covering layers,the failure mode is the local sliding inside the landfill,and the effect of near-slope leachate drainage on the stability control is obvious.
基金The National Key R&D Program of China under contract No.2021YFC3101301the Innovative Academy of Marine Information Technology+6 种基金Chinese Academy of Sciences under contract No.CXBS202101the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)under contract No.GML2019ZD0304the National Natural Science Foundation of China under contract Nos 41876022,41876023,11772111 and91952101the Guangdong Natural Science Foundation of China under contract Nos 1914050004866 and 2020A1515011094the Hong Kong Research Grants Council under contract Nos 16301719 and N-HKUST604/19the Science,Technology and Innovation Commission of Shenzhen Municipality under contract No.KQJSCX20180328165817522the Science and Technology Program of Guangzhou under contract No.202102020707。
文摘We report field measurements of vertical profiles of the turbulent diffusivity and temperature at different stations in the South China Sea(SCS).Our study shows that the measured turbulent diffusivity follows a power-law distribution with a varying exponent in water layers.Similar multiple-layer scaling regimes were also observed from the temperature fluctuations.Combining turbulent diffusivity and temperature fluctuations,the vertical structure of temperature was revealed.Furthermore,we discussed the temperature profiles in each layer.A constant function of a dimensionless temperature profile was found in water layers that have identical turbulence conditions.Our results reveal the multiple-layer structure of temperature in the SCS.This study contributes to the understanding of the vertical structure of multiple layers in the SCS and provides clues for exploring the physical mechanism for maintaining the temperature structure.
文摘Natural frequency characteristics of a thin-walled multiple layered cylindrical shell under lateral pressure are studied. The multiple layered cylindrical shell configuration is formed by three layers of isotropic material where the inner and outer layers are stainless steel and the middle layer is aluminum. The multiple layered shell equations with lateral pressure are established based on Love's shell theory. The governing equations of motion with lateral pressure are employed by using energy functional and applying the Ritz method. The boundary conditions represented by end conditions of the multiple layered cylindrical shell are simply supported-clamped(SS-C), free-clamped(F-C) and simply supported-free(SS-F). The influence of different lateral pressures, different thickness to radius ratios, different length to radius ratios and effect of the asymmetric boundary conditions on natural frequency characteristics are studied. It is shown that the lateral pressure has effect on the natural frequency of multiple layered cylindrical shell and causes the natural frequency to increase. The natural frequency of the developed multilayered cylindrical shell is validated by comparing with those in the literature. The proposed research provides an effective approach for vibration analysis shell structures subjected to lateral pressure with an energy method.
文摘A series of white phosphorescent OLED devices with buffer layer and multiple dopant structure is investigated in order to obtain better electro-optic performances and color stability. The color coordinate and color stability are related to the location of multiple dopants layer, and the optimized location can compensate for the change of the blue emission intensity under a high voltage and stabilize the spectrum. The electro-optic performances and color stability can be further improved by changing the composition and thickness of the buffer layer between the emitting layer and the electron transport layer.In device B2, the distance from multiple dopant layer to buffer layer is 2 nm and the thickness of buffer layer is 5 nm,the maximum luminance, current density, and power efficiency can reach 9091 cd/m^2, 364.5 mA/cm^2, and 26.74 lm/W,respectively. The variation of international commission on the illumination(CIE) coordinate of device B2 with voltage increasing from 4 V to 7 V is only(0.006, 0.004).
文摘In this paper, we reveal the multiple boundary layer phenomena of the solution of nonlinear higher order elliptic equations with perturbation both in boundary and in operator, and provide a method to find uniformly valid asymptotic solution of arbitrary order for these types of problems.
文摘The method of boundary layer with multiple scales and computer algebra were applied to study the asymptotic behavior of solution of boundary value problems for a class of system of nonlinear differential equations . The asymptotic expansions of solution were constructed. The remainders were estimated. And an example was analysed. It provides a new foreground for the application of the method of boundary layer with multiple scales .
文摘Dear Sir,Ifound the article by Sobac1etal[1]very interesting.The authors concluded that repeated intravitreal injection(IVI)of ranibizumab or bevacizumab didn’t seem have adverse effects on retinal nerve fiber layer(RNFL)thickness in wet age-related macular degeneration(AMD)patients.
基金supported by the National Key R&D Program of China(Grant No.2018YFA0704300)the Natural Science Foundation of Jiangsu Province of China(Grant No.BK20201285).
文摘The multiple absorber layer perovskite solar cells(PSCs)with charge transport layers-free(CTLs-free)have drawn widespread research interest due to their simplified architecture and promising photoelectric characteristics.Under the circumstances,the novel design of CTLs-free inversion PSCs with stable and nontoxic three absorber layers(triple Cs_(3)Bi_(2)I_(9),single MASnI_(3),double Cs_(2)TiBr_(6))as optical-harvester has been numerically simulated by utilizing wxAMPS simulation software and achieved high power conversion efficiency(PCE)of 14.8834%.This is owing to the innovative architecture of PSCs favors efficient transport and extraction of more holes and the slender band gap MASnI_(3)extends the absorption spectrum to the near-infrared periphery compared with the two absorber layers architecture of PSCs.Moreover,the performance of the device with p-type-Cs_(3)Bi_(2)I_(9)/p-type-MASnI_(3)/n-type-Cs_(2)TiBr_(6)architecture is superior to the one with the p-type-Cs_(3)Bi_(2)I_(9)/ntype-MASnI_(3)/n-type-Cs_(2)TiBr_(6)architecture due to less carrier recombination and higher carrier life time inside the absorber layers.The simulation results reveal that Cs_(2)TiF_(6)double perovskite material stands out as the best alternative.Additionally,an excellent PCE of 21.4530%can be obtained with the thicker MASnI_(3)absorber layer thickness(0.4μm).Lastly,the highestperformance photovoltaic devices(28.6193%)can be created with the optimized perovskite doping density of around E15 cm^(3)(Cs_(3)Bi_(2)I_(9)),E18 cm^(3)(MASnI_(3)),and 1.5E19 cm^(3)(Cs_(2)TiBr_(6)).This work manifests that the proposed CTLs-free PSCs with multi-absorber layers shall be a relevant reference for forward applications in electro-optical and optoelectronic devices.
文摘In this paper, we study the multiple boundary layer phenomena of solution ofboundary value problem for third order semilinear ordinary differential equationwith two small parameters. Under suitable conditions, using the method of differential inequalities, we prove the existence of solution and give its estimation of remmainder term.
基金Supported by Natural Sci.Fund of Anhui Education Office under contract No.KJ2007A013.
文摘In this paper, we study the singular perturbation of boundary value problem for a class of n-th order nonlinear differential equation, the solution is shown to exhibit multiple layer behavior. According to different layers and by introducing extended variable, we obtain the uniformly effective asymptotic expansion with different boundary layer correction term.
基金supported by the Natural Science Foundation of Zhejiang Province(Nos.LQ21F020021 and LZ21F020008)Zhejiang Provincial Natural Science Foundation of China(No.LZ22F020002)the Research Start-up Project funded by Hangzhou Normal University(No.2020QD2035).
文摘Service recommendation provides an effective solution to extract valuable information from the huge and ever-increasing volume of big data generated by the large cardinality of user devices.However,the distributed and rich multi-source big data resources raise challenges to the centralized cloud-based data storage and value mining approaches in terms of economic cost and effective service recommendation methods.In view of these challenges,we propose a deep neural collaborative filtering based service recommendation method with multi-source data(i.e.,NCF-MS)in this paper,which adopts the cloud-edge collaboration computing paradigm to build recommendation model.More specifically,the Stacked Denoising Auto Encoder(SDAE)module is adopted to extract user/service features from auxiliary user profiles and service attributes.The Multiple Layer Perceptron(MLP)module is adopted to integrate the auxiliary user/service features to train the recommendation model.Finally,we evaluate the effectiveness of the NCF-MS method on three public datasets.The experimental results show that our proposed method achieves better performance than existing methods.
文摘Motivated by the autopilot of an unmanned aerial vehicle(UAV) with a wide flight envelope span experiencing large parametric variations in the presence of uncertainties, a fuzzy adaptive tracking controller(FATC) is proposed. The controller consists of a fuzzy baseline controller and an adaptive increment, and the main highlight is that the fuzzy baseline controller and adaptation laws are both based on the fuzzy multiple Lyapunov function approach, which helps to reduce the conservatism for the large envelope and guarantees satisfactory tracking performances with strong robustness simultaneously within the whole envelope. The constraint condition of the fuzzy baseline controller is provided in the form of linear matrix inequality(LMI), and it specifies the satisfactory tracking performances in the absence of uncertainties. The adaptive increment ensures the uniformly ultimately bounded(UUB) predication errors to recover satisfactory responses in the presence of uncertainties. Simulation results show that the proposed controller helps to achieve high-accuracy tracking of airspeed and altitude desirable commands with strong robustness to uncertainties throughout the entire flight envelope.