Entity

Time filter

Source Type


Chen P.,National Chung Cheng University | Wang C.-H.,National Space Organization NSPO | Ho J.-R.,National Central University
Computers and Mathematics with Applications | Year: 2013

A first-order extended lattice Boltzmann (LB) model with special forcing terms for one-dimensional Maxwell equations exerting on a dispersive medium, described either by the Debye or Drude model, is proposed in this study. The time dependent dispersive effect is obtained by the inverse Fourier transform of the frequency-domain permittivity and is incorporated into the LB evolution equations via equivalent forcing effects. The Chapman-Enskog multi-scale analysis is employed to ensure that proposed scheme is mathematically consistent with the targeted Maxwell's equations at the macroscopic limit. Numerical validations are executed through simulating four representative cases to obtain their LB solutions and compare those with the analytical solutions and existing numerical solutions by finite difference time domain (FDTD). All comparisons show that the differences in numerical values are very small. The present model can thus accurately predict the dispersive effects, and demonstrate first order convergence. In addition to its accuracy, the proposed LB model is also easy to implement. Consequently, this new LB scheme is an effective approach for numerical modeling of EM waves in dispersive media. © 2013 Elsevier Ltd. All rights reserved. Source


Chan S.-C.,National Tsing Hua University | Chen C.-R.,National Space Organization NSPO | Liu C.-H.,National Tsing Hua University
Sensors and Actuators, A: Physical | Year: 2010

With the increasing demand for thermal management in electronic cooling applications, the development of heat dissipation devices has become extremely important. This paper presents the development of a novel bubble-activated micropump with high-frequency flow reversal using embedded electrodes in a closed fluidic microchannel. This bubble-activated micropump consists of a microfluidic chamber structure and microelectrodes on a glass substrate that is assembled using a polydimethylsiloxane (PDMS) elastic sheet. First, the bubble-activated micropump was fabricated on a silicon substrate by spin-coating, curing, and molding using negative photoresist SU-8 2035 as the mold material. Second, a phosphate buffer solution (PBS) was introduced into the micropump chamber to increase the heat dissipation rate via a bubble-based actuator oscillating at a frequency of 300 Hz. The measured maximum flow rate was 37.8 μL/min at an applied voltage of 5 V. This study furthers the development of cooling systems using a bubble-activated design by achieving stable performance. © 2010 Elsevier B.V. All rights reserved. Source


Peng T.-S.,National Taiwan University | Huang Y.-W.,National Taiwan University | Wang L.A.,National Taiwan University | Liu R.-Y.,National Space Organization NSPO | Chou F.-I.,National Tsing Hua University
IEEE Transactions on Nuclear Science | Year: 2010

Two erbium doped fibers (EDFs) with different radiation sensitivities were used in the photo-annealing tests, and their photo-annealing efficiencies were compared by using 532-nm and 976-nm lasers. For both EDFs, the 532-nm laser with 10 mW showed better efficiency than 976-nm laser with 290 mW. The radiation induced attenuation (RIA) could nearly be diminished in the wavelength range from 900 nm to 1700 nm by the photo-annealing of 532-nm laser. The half-time of recovery was 5.6 seconds by using 532-nm laser, and was about 40 minutes by using 976-nm laser whose annealing rate was similar to that of purely thermal annealing at about 330° C. For γ -irradiation tests of superfluorescent fiber sources (SFSs) exposed to a dose rate of 129.2 krad/hr, the rate of output power loss could be reduced by the 976-nm pump laser, but the output power loss could not be recovered. A most radiation-tolerant case was an SFS with 2.8-meter EDF#1 co-pumped by both the 532 nm and the 976 nm lasers. The output power loss could be recovered with a rate of 0.009 dB/min. © 2010 IEEE. Source


Peng T.-S.,National Taiwan University | Wang L.A.,National Taiwan University | Liu R.-Y.,National Space Organization NSPO
IEEE Photonics Technology Letters | Year: 2011

A novel feedback control method by tuning reflectivity was demonstrated for stabilizing mean-wavelength of a double-pass backward (DPB) superfluorescent fiber source (SFS) under 60 Co irradiation. The mean-wavelength drift was compensated with increasing dose up to 22 krad, suitable for the applications in the low Earth orbit. The rate of output power loss induced by irradiation could be decreased by 33% when the feedback control was working. The linewidth of the DPB SFS was 16 nm, 1.6 times larger than the reported one by adding an output edge filter. With such a larger linewidth the angle random walk (ARW) of an IFOG can be more reduced. © 2011 IEEE. Source


Chang C.-L.,National Space Organization NSPO | Fu L.-Y.,National Tsing Hua University
34th Asian Conference on Remote Sensing 2013, ACRS 2013 | Year: 2013

This study assesses the effects of science and culture learning through an innovative tribal tourism developed in Atayal Satellite Program. The purposes of this tourism model are using indigenous-culture tourism to develop the tribal economy, promoting a leisure activity for learning satellite basics and applications and developing a sustainable environment for indigenous tourism. The model is feasible according to quantitative analysis of Test of Science Related Attitudes (TOSRA), the other questionnaires and interviews with tribal villagers, who took part in the program, and participants, who participated in the camps. The study reveals positive responses to the activities of the Atayal Satellite Program and significantly positive effects of science and culture learning in the Atayal Satellite Program. Source

Discover hidden collaborations