In past years,growing efforts have been made to the rapid interpretation of magnetic field data acquired by a sparse synthetic or real magnetic sensor array.An appealing requirement on such sparse array arranged withi...In past years,growing efforts have been made to the rapid interpretation of magnetic field data acquired by a sparse synthetic or real magnetic sensor array.An appealing requirement on such sparse array arranged within a specified survey region is that to make the number of sensor elements as small as possible,meanwhile without deteriorating imaging quality.For this end,we propose a novel methodology of arranging sensors in an optimal manner,exploring the concept of information capacity developed originally in the communication society.The proposed scheme reduces mathematically the design of a sparse sensor array into solving a combinatorial optimization problem,which can be resolved efficiently using widely adopted Simultaneous Perturbation and Statistical Algorithm(SPSA).Three sets of numerical examples of designing optimal sensor array are provided to demonstrate the performance of proposed methodology.展开更多
We report a method for the coacervation micro-encapsulation of several forms of CaCO3 microparticles with the fluoropolymer poly(heptadecafluorodecyl acrylate) (poly (HDFDA)) by pressure-induced phase separation of a ...We report a method for the coacervation micro-encapsulation of several forms of CaCO3 microparticles with the fluoropolymer poly(heptadecafluorodecyl acrylate) (poly (HDFDA)) by pressure-induced phase separation of a supercritical CO2 solution.? A suspension of CaCO3 in CO2 and dissolved poly(HDFDA) were mixed in supercritical CO2.? After the system pressure was slowly decreased to atmospheric pressure, the microcapsules were obtained.? Coacervation was achieved by the precipitation of poly(HDFDA) during the decrease in the pressure of CO2;the solubility of poly(HDFDA) in CO2 decreased with the pressure.? The structure and morphology of the microparticles were investigated by using a scanning electron microscope (SEM) and an electron probe microanalyzer (EPMA) equipped with a wavelength dispersive X-ray spectroscope (WDX).展开更多
Recently,high di/dt and dv/dt switching operations of power converter circuits has been discussed for realizing a high-efficiency power converter circuit.In this case,parasitic inductances of the bus bar between a DC ...Recently,high di/dt and dv/dt switching operations of power converter circuits has been discussed for realizing a high-efficiency power converter circuit.In this case,parasitic inductances of the bus bar between a DC capacitor and power devices may cause issues of overshoot voltage and electromagnetic interference(EMI)noise.Therefore,it is necessary to design the bus bar geometry while considering the minimization and optimization of the parasitic inductance of bus bar.This paper discusses a relationship between bus bar geometry and switching characteristics.In addition,the bus bar analysis is based on the PEEC method,and the bus bar geometry is designed by considering the stray inductance with using an inductance-map method.Moreover,this paper also presents a design procedure of acceptable stray inductance based on a standardization method.It should be noted that the stray inductance is designed not for minimization,but optimization,and it is shown not as an absolute value(H),but as a percentage value(%).Finally,the oscillation waveforms under turn-off operation will be discussed depending on the bus bar geometry.展开更多
A couple of simple-structure phase modulators were used in active mode-locked fiber laser to implement repetition rate continuous tuning. The laser produces pulse as short as 5.7 ps whose repetition rate tuning can co...A couple of simple-structure phase modulators were used in active mode-locked fiber laser to implement repetition rate continuous tuning. The laser produces pulse as short as 5.7 ps whose repetition rate tuning can cover the spacing of the adjoining order mode-locking frequencies.展开更多
文摘In past years,growing efforts have been made to the rapid interpretation of magnetic field data acquired by a sparse synthetic or real magnetic sensor array.An appealing requirement on such sparse array arranged within a specified survey region is that to make the number of sensor elements as small as possible,meanwhile without deteriorating imaging quality.For this end,we propose a novel methodology of arranging sensors in an optimal manner,exploring the concept of information capacity developed originally in the communication society.The proposed scheme reduces mathematically the design of a sparse sensor array into solving a combinatorial optimization problem,which can be resolved efficiently using widely adopted Simultaneous Perturbation and Statistical Algorithm(SPSA).Three sets of numerical examples of designing optimal sensor array are provided to demonstrate the performance of proposed methodology.
文摘We report a method for the coacervation micro-encapsulation of several forms of CaCO3 microparticles with the fluoropolymer poly(heptadecafluorodecyl acrylate) (poly (HDFDA)) by pressure-induced phase separation of a supercritical CO2 solution.? A suspension of CaCO3 in CO2 and dissolved poly(HDFDA) were mixed in supercritical CO2.? After the system pressure was slowly decreased to atmospheric pressure, the microcapsules were obtained.? Coacervation was achieved by the precipitation of poly(HDFDA) during the decrease in the pressure of CO2;the solubility of poly(HDFDA) in CO2 decreased with the pressure.? The structure and morphology of the microparticles were investigated by using a scanning electron microscope (SEM) and an electron probe microanalyzer (EPMA) equipped with a wavelength dispersive X-ray spectroscope (WDX).
文摘Recently,high di/dt and dv/dt switching operations of power converter circuits has been discussed for realizing a high-efficiency power converter circuit.In this case,parasitic inductances of the bus bar between a DC capacitor and power devices may cause issues of overshoot voltage and electromagnetic interference(EMI)noise.Therefore,it is necessary to design the bus bar geometry while considering the minimization and optimization of the parasitic inductance of bus bar.This paper discusses a relationship between bus bar geometry and switching characteristics.In addition,the bus bar analysis is based on the PEEC method,and the bus bar geometry is designed by considering the stray inductance with using an inductance-map method.Moreover,this paper also presents a design procedure of acceptable stray inductance based on a standardization method.It should be noted that the stray inductance is designed not for minimization,but optimization,and it is shown not as an absolute value(H),but as a percentage value(%).Finally,the oscillation waveforms under turn-off operation will be discussed depending on the bus bar geometry.
文摘A couple of simple-structure phase modulators were used in active mode-locked fiber laser to implement repetition rate continuous tuning. The laser produces pulse as short as 5.7 ps whose repetition rate tuning can cover the spacing of the adjoining order mode-locking frequencies.
