Sense of touch is one of the important information from environment for human to live in daily life. Haptic interface is a hot topic in virtual reality but almost all of the devices focus on fingers and hands as targe...Sense of touch is one of the important information from environment for human to live in daily life. Haptic interface is a hot topic in virtual reality but almost all of the devices focus on fingers and hands as targets. In this paper, we focus on the foot haptic device with magnetic flied sensitive elastomer （MSE）. We developed a haptic unit used as a magnetic field generator for MSE and contact point of foot haptic device. MSE samples mixed with 80 wt% carbonyl iron particles were prepared and evaluated with the developed magnet. Experimental results show that the mechanical property of the haptic unit can be modeled with the adjustable friction element. This property has a good advantage for the haptic unit.展开更多
The principle and performance of a fiber-optic Faraday-effect magnetic-field sensor based on an yttrium iron garnet (YIG) and two flux concentrations are described. A single polarization-maintaining optical fiber link...The principle and performance of a fiber-optic Faraday-effect magnetic-field sensor based on an yttrium iron garnet (YIG) and two flux concentrations are described. A single polarization-maintaining optical fiber links the sensor head to the source and detection system, in which the technique of phase shift cancellation is used to cancel the phase shift that accumulatein the optical fiber. Flux concentrators were exploited to enhance the YIG crystal magneto-optic sensitivity .The sensor system exhibited a noise-equivalent field of 8 pT/√Hz and a 3 dB bandwidth of ～10 MHz.展开更多
Electromagnetic holographic data are characterized by two modes, suggesting that image reconstruction requires a dual-mode sensitivity field as well. We analyze an electromagnetic holographic field based on tomography...Electromagnetic holographic data are characterized by two modes, suggesting that image reconstruction requires a dual-mode sensitivity field as well. We analyze an electromagnetic holographic field based on tomography theory and Radon inverse transform to derive the expression of the electromagnetic holographic sensitivity field （EMHSF）. Then, we apply the EMHSF calculated by using finite-element methods to flow simulations and holographic imaging. The results suggest that the EMHSF based on the partial derivative of radius of the complex electric potential φ is closely linked to the Radon inverse transform and encompasses the sensitivities of the amplitude and phase data. The flow images obtained with inversion using EMHSF better agree with the actual flow patterns. The EMHSF overcomes the limitations of traditional single-mode sensitivity fields.展开更多
NiFeCr/NiFe/Ta films with excellent performance were prepared by magnetron sputtering system.The anisotropic magetoresistance (AMR) value (ΔR/R) and magnetic filed sensitivity (Sv,Sv=[d(ΔR/R)/dH]max.) for the 12 nm ...NiFeCr/NiFe/Ta films with excellent performance were prepared by magnetron sputtering system.The anisotropic magetoresistance (AMR) value (ΔR/R) and magnetic filed sensitivity (Sv,Sv=[d(ΔR/R)/dH]max.) for the 12 nm NiFe film deposited on NiFeCr buffer layer were 3.66% and 1.42×10-4%·T-1,respectively.The higher Sv of the film is close to that of a spin valve (SV).The microstructure analysis shows that the NiFeCr buffer layer has adopted the same structure with the same interplanar distance as the NiFe layer,inducing a strong NiFe (111) texture,and that the NiFeCr/NiFe interface is quite smooth,leading to a high degree of specular reflection of conduction electrons.Both increase the ΔR and reduce the R in the film,which lead to the high ΔR/R.Clean substrate surfaces are critical for preparation of high performance NiFeCr/NiFe/Ta films,and sputter cleaning or pre-deposition of 5 nm amorphous Al2O3 layer in the deposition chamber can provide the re-quired clean substrate surfaces for the growth of the buffer layer.展开更多
For complicated geometries, it is ineflicient to integrate over the entire domain. A new approach for optimization is presented here, based on sensitivity analysis of local do- main and deformation of full domain. Acc...For complicated geometries, it is ineflicient to integrate over the entire domain. A new approach for optimization is presented here, based on sensitivity analysis of local do- main and deformation of full domain. Accurate results of design sensitivity analysis are ob- tained with this approach in shape optimization. This method is shown to be efficient when used in optimization programs and results in less distortion of the mesh.展开更多
This paper presents a novel capacitance probe, i.e., paraUel-wire capacitance probe （PWCP）, for two-phase flow measurement. Using finite element method （FEM）, the sensitivity field of the PWCP is investigated and ...This paper presents a novel capacitance probe, i.e., paraUel-wire capacitance probe （PWCP）, for two-phase flow measurement. Using finite element method （FEM）, the sensitivity field of the PWCP is investigated and the optimum sensor geometry is determiend in term of the characterisitc parameters. Then, the response of PWCP for the oil-water stratified flow is calculated, and it is found the PWCP has better linearity and sensitivity to the variation of water-layer thickness, and is almost independant of the angle between the oil-water interface and the sensor electrode. Finally, the static experiment for oil-water stratified flow is carried out and the calibration method of liquid holdup is presented.展开更多
Smart polymers have enormous potential in various applications.In particular,smart polymeric drug delivery systems have been explored as“intelligent”delivery systems able to release,at the appropriate time and site ...Smart polymers have enormous potential in various applications.In particular,smart polymeric drug delivery systems have been explored as“intelligent”delivery systems able to release,at the appropriate time and site of action,entrapped drugs in response to specific physiological triggers.These polymers exhibit a non-linear response to a small stimulus leading to a macroscopic alteration in their structure/properties.The responses vary widely from swelling/contraction to disintegration.Synthesis of new polymers and crosslinkers with greater biocompatibility and better biodegradability would increase and enhance current applications.The most fascinating features of the smart polymers arise from their versatility and tunable sensitivity.The most significant weakness of all these external stimuli-sensitive polymers is slow response time.The versatility of polymer sources and their combinatorial synthesis make it possible to tune polymer sensitivity to a given stimulus within a narrow range.Development of smart polymer systems may lead to more accurate and programmable drug delivery.In this review,we discuss various mechanisms by which polymer systems are assembled in situ to form implanted devices for sustained release of therapeutic macromolecules,and we highlight various applications in the field of advanced drug delivery.展开更多
文摘Sense of touch is one of the important information from environment for human to live in daily life. Haptic interface is a hot topic in virtual reality but almost all of the devices focus on fingers and hands as targets. In this paper, we focus on the foot haptic device with magnetic flied sensitive elastomer （MSE）. We developed a haptic unit used as a magnetic field generator for MSE and contact point of foot haptic device. MSE samples mixed with 80 wt% carbonyl iron particles were prepared and evaluated with the developed magnet. Experimental results show that the mechanical property of the haptic unit can be modeled with the adjustable friction element. This property has a good advantage for the haptic unit.
文摘The principle and performance of a fiber-optic Faraday-effect magnetic-field sensor based on an yttrium iron garnet (YIG) and two flux concentrations are described. A single polarization-maintaining optical fiber links the sensor head to the source and detection system, in which the technique of phase shift cancellation is used to cancel the phase shift that accumulatein the optical fiber. Flux concentrators were exploited to enhance the YIG crystal magneto-optic sensitivity .The sensor system exhibited a noise-equivalent field of 8 pT/√Hz and a 3 dB bandwidth of ～10 MHz.
基金supported by the National Science and Technology Major Project(No.2011ZX05020-006)
文摘Electromagnetic holographic data are characterized by two modes, suggesting that image reconstruction requires a dual-mode sensitivity field as well. We analyze an electromagnetic holographic field based on tomography theory and Radon inverse transform to derive the expression of the electromagnetic holographic sensitivity field （EMHSF）. Then, we apply the EMHSF calculated by using finite-element methods to flow simulations and holographic imaging. The results suggest that the EMHSF based on the partial derivative of radius of the complex electric potential φ is closely linked to the Radon inverse transform and encompasses the sensitivities of the amplitude and phase data. The flow images obtained with inversion using EMHSF better agree with the actual flow patterns. The EMHSF overcomes the limitations of traditional single-mode sensitivity fields.
基金supported by the National Science Foundation of China (No.50671008,50871014,50831002,50971021,and 50101012)
文摘NiFeCr/NiFe/Ta films with excellent performance were prepared by magnetron sputtering system.The anisotropic magetoresistance (AMR) value (ΔR/R) and magnetic filed sensitivity (Sv,Sv=[d(ΔR/R)/dH]max.) for the 12 nm NiFe film deposited on NiFeCr buffer layer were 3.66% and 1.42×10-4%·T-1,respectively.The higher Sv of the film is close to that of a spin valve (SV).The microstructure analysis shows that the NiFeCr buffer layer has adopted the same structure with the same interplanar distance as the NiFe layer,inducing a strong NiFe (111) texture,and that the NiFeCr/NiFe interface is quite smooth,leading to a high degree of specular reflection of conduction electrons.Both increase the ΔR and reduce the R in the film,which lead to the high ΔR/R.Clean substrate surfaces are critical for preparation of high performance NiFeCr/NiFe/Ta films,and sputter cleaning or pre-deposition of 5 nm amorphous Al2O3 layer in the deposition chamber can provide the re-quired clean substrate surfaces for the growth of the buffer layer.
文摘For complicated geometries, it is ineflicient to integrate over the entire domain. A new approach for optimization is presented here, based on sensitivity analysis of local do- main and deformation of full domain. Accurate results of design sensitivity analysis are ob- tained with this approach in shape optimization. This method is shown to be efficient when used in optimization programs and results in less distortion of the mesh.
基金Supported by the National Natural Science Foundation of China （50974095, 41174109, 61104148）, and the National Science and Technology Mai or Projects （2011ZX05020-006）.
文摘This paper presents a novel capacitance probe, i.e., paraUel-wire capacitance probe （PWCP）, for two-phase flow measurement. Using finite element method （FEM）, the sensitivity field of the PWCP is investigated and the optimum sensor geometry is determiend in term of the characterisitc parameters. Then, the response of PWCP for the oil-water stratified flow is calculated, and it is found the PWCP has better linearity and sensitivity to the variation of water-layer thickness, and is almost independant of the angle between the oil-water interface and the sensor electrode. Finally, the static experiment for oil-water stratified flow is carried out and the calibration method of liquid holdup is presented.
文摘Smart polymers have enormous potential in various applications.In particular,smart polymeric drug delivery systems have been explored as“intelligent”delivery systems able to release,at the appropriate time and site of action,entrapped drugs in response to specific physiological triggers.These polymers exhibit a non-linear response to a small stimulus leading to a macroscopic alteration in their structure/properties.The responses vary widely from swelling/contraction to disintegration.Synthesis of new polymers and crosslinkers with greater biocompatibility and better biodegradability would increase and enhance current applications.The most fascinating features of the smart polymers arise from their versatility and tunable sensitivity.The most significant weakness of all these external stimuli-sensitive polymers is slow response time.The versatility of polymer sources and their combinatorial synthesis make it possible to tune polymer sensitivity to a given stimulus within a narrow range.Development of smart polymer systems may lead to more accurate and programmable drug delivery.In this review,we discuss various mechanisms by which polymer systems are assembled in situ to form implanted devices for sustained release of therapeutic macromolecules,and we highlight various applications in the field of advanced drug delivery.
