Browsing by Author "Lin, Yu-Pin"

Now showing 1 - 12 of 12

A frequency domain based TEQ design for DSL systems
(2006)
Lin, Yuan-Pei
;
Lin, Yu-Pin
;
Phoong, See-May
;
電控工程研究所
;
Institute of Electrical and Control Engineering
In this paper, we propose a frequency domain based design method for designing TEQ (time domain equalizer) for DSL (digital subscriber loops) applications. In DSL applications, usually frequency division multiplexing is used to separate the upstream and downstream signals. In either direction of transmission, some of the frequency bands are not used for transmission. Interference is formulated and minimized in the frequency domain to take advantage of the unused frequency bands. The frequency domain approach allows us to have a more direct control over the frequency response of the resulting TEQ, which is crucial in the final achievable transmission bit rates. The simulation examples demonstrate that the proposed method shortens the channel effectively and very good transmission bit rates can be achieved.
Application of System Dynamics on Shallow Multipurpose Artificial Lakes: A Case Study of Detention Pond at Tainan, Taiwan
(2010-06-01)
Chu, Hone-Jay
;
Chang, Liang-Cheng
;
Lin, Yu-Pin
;
Wang, Yung-Chieh
;
Chen, Yu-Wen
This study designs a multipurpose urban shallow artificial lake, including water supply, flood detention, and water environment preservation. It is expected to not only preserve a healthy water environment but to also retain water conservation and flood detention. This study adopts system dynamics (SD) to analyze the relationship between different purposes of water resources utilization. Furthermore, different operation strategies effects can be simulated by SD through a proposed urban multipurpose shallow artificial lake system. The results demonstrate the dynamic effects of strategies managers propose such as demand analysis, inflow control, and water quality improvement in this case study for Taiwan. SD aids lake system prediction and understanding temporally in sequential planning for water supply, environmental preservation, and flood detention. The SD model will hopefully serve as a reference to study different features before artificial lakes constructing.
Characteristics of Cu2ZnSn(SXSe1-x)(4) thin-film solar cells prepared by sputtering deposition using single quaternary Cu2ZnSnS4 target followed by selenization/sulfurization treatment
(2017-04)
Lin, Yu-Pin
;
Hsieh, Tsung-Eong
;
Chen, Yen-Chih
;
Huang, Kun-Ping
;
材料科學與工程學系
This work demonstrates the preparation of Cu2ZnSn(SxSe1-x)(4)(CZTSSe) thin films by sputtering deposition using single-phase Cu2ZnSnS4 (CZTS) target followed by selenization/sulfurization treatment at 570 degrees C for 1 h. Afterward, the CZTSSe thin-film solar cell samples with the Mo/CZTSSe/CdS/i-ZnO/IZO/Al structure were prepared and their performances were evaluated. By varying the ratio of Se and S powders of heat treatment, the Cu-poor/Zn-rich CZTSSe layers with S/(S+Se) ratio in the range of 0.21-1 were achieved and the CZTSSe layers were the mixture of kesterite CZTS and CZTSe phases as revealed by the x-ray diffraction and the Raman spectroscopy analyses. UV-NIR spectroscopy indicated the bandgaps of CZTSSe samples are in the range of 1.06-1.45 eV when the S/(S+Se) ratio varies from 0.21 to 1. Hall measurement observed the best transport property with p-type carrier concentration of 2.17x10(15) cm(-3) and mobility of 8.9 cm(2) V-1 sec(-1) in CZTSSe layer with S/(S+Se) ratio of 0.46. Under the AM1.5 illumination condition, the CZTSSe thin-film solar cell sample with S/(S+Se) ratio of 0.46 exhibited the best performance with open-circuit voltage of 0.506 V, short-circuit current density of 27.41 mA/cm(2), fill factor of 50% and conversion efficiency of 6.9%.
Epitaxial Yttria-Stabilized Zirconia on Muscovite for Flexible Transparent Ionic Conductors
(2018-12-01)
Wu, Ping-Chun
;
Lin, Yu-Pin
;
Juan, Yung-Hsiang
;
Wang, Yao-Ming
;
Do Thi-Hien
The advantages of ionic conductors have attracted great interest worldwide because they can fit the requirements that standard electrical conductors struggle to meet. Yttria-stabilized zirconia (YSZ) is the most common ionic conductor for various practical applications. In this study, in order to bring ionic conductors into the field of soft technology, transparent YSZ films with superior mechanical flexibility were epitaxially grown on a muscovite substrate by pulsed-laser deposition. The epitaxial relationship between YSZ and muscovite has been well established, indicating a high-crystallinity thin film. The heterostructure of YSZ/muscovite exhibits excellent ionic conductivity with great mechanical flexibility. The smallest bending radius of this heterostructure that can be achieved is similar to 10 mm with excellent mechanical cyclabilty (>800 cycles) and stability (>10(5) s), serving as a new platform to fabricate highly flexible ionic conductors.
Fabrication of Multilayer Borophene on Insulator Structure
(2016-10-12)
Tsai, Hsu-Sheng
;
Hsiao, Ching-Hung
;
Lin, Yu-Pin
;
Chen, Chia-Wei
;
Ouyang, Hao
Formation of gradient Ga distribution in Cu(In,Ga)Se-2 thin-film solar cells prepared by (InGa)(2)Se-3/CuInGaSe2 stacking structure followed by Se-Vapor selenization
(2018-09-15)
Lin, Yu-Pin
;
Hsieh, Tsung-Eong
;
Chen, Yen-Chih
;
Huang, Kun-Ping
;
材料科學與工程學系
Cu(In,Ga)Se-2 (CIGS) light absorption layers with gradient Ga distribution were prepared by utilizing the sequential deposition of (InGa)(2)Se-3 (IGS) and CIGS layers. The IGS buffer layers were deposited on Mo/soda lime glass substrate at various working pressures (WP = 1, 10 and 30 mtorr) followed by the deposition of CIGS layers. Afterward, the microstructures and compositions of CIGS layers formed by the selenization of CIGS/IGS stacking layers in Se vapor ambient at 560 degrees C for 1 h were investigated. The CIGS layer with the optimized microstructure and transport properties was then implanted in the thin-film solar cells and the device with the best conversion efficiency of 8.22 +/- 0.0754% was achieved. The satisfactory solar cell performance was ascribed to the insertion of IGS layer which remedies the deficiency of In, Ga and Se elements and forms the gradient Ga distribution in CIGS layer as revealed by the secondary ion mass spectroscopy.
Geostatistical approaches and optimal additional sampling schemes for spatial patterns and future sampling of bird diversity
(2008-03-01)
Lin, Yu-Pin
;
Yeh, Ming-Sheng
;
Deng, Dong-Po
;
Wang, Yung-Chieh
;
土木工程學系
Aim To evaluate geostatistical approaches, namely kriging, co-kriging and geostatistical simulation, and to develop an optimal sampling design for mapping the spatial patterns of bird diversity, estimating their spatial autocorrelations and selecting additional samples of bird diversity in a 2450 km(2) basin. Location Taiwan. Methods Kriging, co-kriging and simulated annealing are applied to estimate and simulate the spatial patterns of bird diversity. In addition, kriging and co-kriging with a genetic algorithm are used to optimally select further samples to improve the kriging and co-kriging estimations. The association between bird diversity and elevation, and bird diversity and land cover, is analysed with estimated and simulated maps. Results The Simpson index correlates spatially with the normalized difference vegetation index (NDVI) within the micro-scale and the macro-scale in the study basin, but the Shannon diversity index only correlates spatially with NDVI within the micro-scale. Co-kriging and simulated annealing simulation accurately simulate the statistical and spatial patterns of bird diversity. The mean estimated diversity and the simulated diversity increase with elevation and decrease with increasing urbanization. The proposed optimal sampling approach selects 43 additional sampling sites with a high spatial estimation variance in bird diversity. Main conclusions Small-scale variations dominate the total spatial variation of the observed diversity due to a lack of spatial information and insufficient sampling. However, simulations of bird diversity consistently capture the sampling statistics and spatial patterns of the observed bird diversity. The data thus accumulated can be used to understand the spatial patterns of bird diversity associated with different types of land cover and elevation, and to optimize sample selection. Co-kriging combined with a genetic algorithm yields additional optimal sampling sites, which can be used to augment existing sampling points in future studies of bird diversity.
Groundwater Simulations and Uncertainty Analysis Using MODFLOW and Geostatistical Approach with Conditioning Multi-Aquifer Spatial Covariance
(2017-03-01)
Lin, Yu-Pin
;
Chen, Yu-Wen
;
Chang, Liang-Cheng
;
Yeh, Ming-Sheng
;
Huang, Guo-Hao
This study presents an approach for obtaining limited sets of realizations of hydraulic conductivity (K) of multiple aquifers using simulated annealing (SA) simulation and spatial correlations among aquifers to simulate realizations of hydraulic heads and quantify their uncertainty in the Pingtung Plain, Taiwan. The proposed approach used the SA algorithm to generate large sets of natural logarithm hydraulic conductivity (ln(K)) realizations in each aquifer based on spatial correlations among aquifers. Moreover, small sets of ln(K) realizations were obtained from large sets of realizations by ranking the differences among cross-variograms derived from the measured ln(K) and the simulated ln(K) realizations between the aquifer pair Aquifer 1 and Aquifer 2 (hereafter referred to as Aquifers 1-2) and the aquifer pair Aquifer 2 and Aquifer 3 (hereafter referred to as Aquifers 2-3), respectively. Additionally, the small sets of realizations of the hydraulic conductivities honored the horizontal spatial variability and distributions of the hydraulic conductivities among aquifers to model groundwater precisely. The uncertainty analysis of the 100 combinations of simulated realizations of hydraulic conductivity was successfully conducted with generalized likelihood uncertainty estimation (GLUE). The GLUE results indicated that the proposed approach could minimize simulation iterations and uncertainty, successfully achieve behavioral simulations when reduced between calibration and evaluation runs, and could be effectively applied to evaluate uncertainty in hydrogeological properties and groundwater modeling, particularly in those cases which lack three-dimensional data sets yet have high heterogeneity in vertical hydraulic conductivities.
Monitoring and estimating the flow conditions and fish presence probability under various flow conditions at reach scale using genetic algorithms and kriging methods
(2011-02-10)
Lin, Yu-Pin
;
Wang, Cheng-Long
;
Yu, Hsiao-Hsuan
;
Huang, Chung-Wei
;
Wang, Yung-Chieh
The combination of current velocity and water depth influences stream flow conditions, and fish activities prefer particular flow conditions. This study develops a novel optimal flow classification method for identifying types of stream flow based on the current velocity and the water depth using a genetic algorithm. It is applied to the Datuan stream in northern Taiwan. Fish were sampled and their habitat investigated at the study site during the spring, summer, fall and winter of 2008-2009. The current velocity, water depth and maps of the presence probability of fish were estimated by ordinary and indicator kriging. The optimal classification results were compared with the classification results obtained using the Froude number and empirical methods. The flow classification results demonstrate that the proposed optimal flow classification method that considers depth-velocity and optimally identified criteria for classifying flow types, yields a current velocity and water depth of 0.32 (m/s) and 0.29 (m), respectively, and classifies the flow conditions in the study area as pool, run, riffle and slack The variography results of the current velocity and the water depth data reveal that seasonal flows are not spatially stationary among seasons in the study area. Kriging methods and a two-dimensional hydrodynamic model (River 2D) with empirical and optimal flow classification methods are more effective than the Froude number method in classifying flow conditions in the study area. The flow condition classifications and probability maps were generated by River 2D, ordinary kriging and indicator kriging, to quantify the flow conditions preferred by Sicyopterus japonicus in the study area. However, the proposed optimal classification method with kriging and River 2D is an effective alternative method for mapping flow conditions and determining the relationship between flow and the presence probability of target fish in support of stream restoration. (C) 2010 Elsevier B.V. All rights reserved.
Preparation of Cu(In,Ga)Se-2 nanoparticles via solvothermal method in conjunction with ball milling process and its applications to thin-film solar cells
(2019-06-30)
Chen, Yen-Chih
;
Lin, Yu-Pin
;
Hsieh, Tsung-Eong
;
Huang, Mei-Wen
;
材料科學與工程學系
Single-phase chalcopyrite CIGS particles with the sizes of 40-60 nm and the stoichiometry of Cu-26(.)01(In17.00Ga8.01)Se-48(.98) were synthesized by the solvothermal method. The CIGS precursor layers were prepared via the doctor-blade coating process utilizing the slurry containing CIGS nanoparticles and the CIGS layers were then formed by a selenization at 540 degrees C for various times in the Se vapor ambient. Microstructure and composition analyses indicated the CIGS layers are of the singe-phase chalcopyrite phase and the Cu-poor composition feature with stoichiometry close to the ideal ratio of 1:1:2. Moreover, the increase of selenization time benefited the coarsening of grain structure in CIGS layer as revealed by the scanning electron microscopy. Accordingly, the CIGS thin-film solar cell samples with the Mo/CIGS/ CdS/i-ZnO/AZO/Ag structure were prepared and their performance were evaluated. Under the AM1.5 illumination condition, the best PV performance with open-circuit voltage of 0.49 V, short-circuit current density of 29.46 mA/cm(2), fill factor of 54% and conversion efficiency of 7.75% was accomplished in the thin-film solar cell sample containing CIGS light absorption layer prepared by the 540 degrees C-selenization for 15 min. (C) 2019 Elsevier B.V. All rights reserved.
Preparation of Cu2ZnSnS4 (CZTS) sputtering target and its application to the fabrication of CZTS thin-film solar cells
(2016-01-05)
Lin, Yu-Pin
;
Chi, Yi-Fang
;
Hsieh, Tsung-Eong
;
Chen, Yen-Chih
;
Huang, Kun-Ping
The CuS, ZnS and SnS2 raw powders were adopted as the starting materials for preparing the 2-inch Cu2ZnSnS4 (CZTS) sputtering target. The powders were mixed at various molar ratios of Cu:Zn:Sn:S = 1.6:1:1:4, 1.8:1:1:4 and 2:1:1:4, pressed into 6-mm pellet forms, and then sintered at different temperatures for 8 h. Accordingly, the influence of powder constitution and heat-treatment conditions on the microstructure, composition and morphology of CZTS pellets were investigated. Microstructure and composition analyses indicated that the sample prepared with the Cu molar ratio of 1.6 and sintered at 600 degrees C for 8 h forms the kesterite CZTS single-phase structure with the Cu-poor/Zn-rich composition. The 2-inch CZTS sputtering target was prepared by utilizing the method established by the study of 6-mm pellets and adopted for depositing the CZTS thin films. The CZTS layer deposited at the working pressure of 1 mtorr followed by the sulfurization at 570 degrees C for 1 h possessed the stoichiometry of Cu24.15Zn14.73Sn10.75S50.37 which is the closest to the ideal stoichiometric ratio of 2:1:1:4. Moreover, it exhibited the bandgap of 1.5 eV, p-type carrier concentration of 2.8 x 1017 cm(-3) and mobility of 8.61 cm(2) V-1 s(-1). Such a CZTS layer was implanted in the thin-film solar cells with the device structure of Mo/CZTS/CdS/i-ZnO/IZO/Al. Under the AM1.5 illumination condition, the CZTS thin-film solar cell sample with the open-circuit voltage of 0.52 V, the short-circuit current density of 19.17 mA/cm(2), the fill factor of 52.7% and the conversion efficiency of 5.2% was achieved. (C) 2015 Published by Elsevier B.V.
Using a hybrid approach to optimize experimental network design for aquifer parameter identification
(2010-10-01)
Chang, Liang-Cheng
;
Chu, Hone-Jay
;
Lin, Yu-Pin
;
Chen, Yu-Wen
;
土木工程學系
This research develops an optimum design model of groundwater network using genetic algorithm (GA) and modified Newton approach, based on the experimental design conception. The goal of experiment design is to minimize parameter uncertainty, represented by the covariance matrix determinant of estimated parameters. The design problem is constrained by a specified cost and solved by GA and a parameter identification model. The latter estimates optimum parameter value and its associated sensitivity matrices. The general problem is simplified into two classes of network design problems: an observation network design problem and a pumping network design problem. Results explore the relationship between the experimental design and the physical processes. The proposed model provides an alternative to solve optimization problems for groundwater experimental design.