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Item type:Item, Examining the large-time wellbore flux of constant head test(2010-09-14) ;Yeh, Hund-Der ;Wang, Chih-Tse ;Smith, Stefan G. Llewellyn ;環境工程研究所Institute of Environmental EngineeringThe function 1/[p ln (p/lambda)] comes from the wellbore flux solution in the Laplace domain for a constant head aquifer test when the Laplace variable p is small. The resulting inverse Laplace transform v(lambda t), representing the large-time wellbore flux, grows exponentially with time, which does not agree with the physical behavior of the wellbore flux. Based on this result, Chen and Stone (1993) asserted that the well-known relationship of small p-large t may fail to yield the correct large-time asymptotic solution. Yeh and Wang (2007) pointed out that the large-time wellbore flux is not n(lambda t) if the inversion of 1/[p ln (p/lambda)] is subject to the constraint Re p > lambda. Chen (2009) subsequently questioned the necessity of imposing this constraint on the Laplace transform in the inversion of the large-time wellbore flux. Motived by Chen's comment, we reexamine the inversion of 1/[p ln (p/lambda)] and demonstrate that this contradictory issue originates from a spurious pole introduced when applying the small p-large t correspondence to the Laplace domain solution. We explain why this occurs and why the actual wellbore flux at large times is proportional to the function N(lambda t), known as Ramanujan's integral. The function N(lambda t) does decay at large time, which agrees with the steady state wellbore flux of the constant head test.Item type:Item, A Thieno[3,4-c]pyrrole-4,6-dione-Based Donor-Acceptor Polymer Exhibiting High Crystallinity for Photovoltaic Applications(2010-09-14) ;Yuan, Mao-Chuan ;Chiu, Mao-Yuan ;Liu, Shih-Pin ;Chen, Chia-MinWei, Kung-HwaItem type:Item, Slope control device capable of predicting uniform-current-sharing level and method thereof(2010-09-14) ;Ho ;Hsin-Hsin ;Chen ;Ke-HorngHsiehThe present invention discloses a slope control device capable of predicting uniform-current-sharing level and method thereof which can be applied in a redundancy or distributed power system for providing better uniform-current-sharing ability. The device comprises a high linearity transconductor circuit, a slope adjusting circuit and an incremental output voltage circuit. The invention applies either a transconductor parameter or a feedback resistor to increase the droop gain and therefore the current deviation between two power supply modules is reduced. The invention further raises the output voltage step by step to ensure that the output voltage meet the requirement of allowable minimum output voltage according to increment of load current.Item type:Item, Capacity-based compressed mode control method for inter-system handover in universal mobile telecommunication system(2010-09-14) ;Huang ;Ching Yao ;Chang ;Cheng TaHoThe Inter-System handover is one of the key features in the third generation cellular systems. The compressed mode, with variable transmission gaps and power levels, is standardized to support the inter-frequency system handover. To minimize the use of system resources while maintaining the border-cell handover quality, a capacity-based compressed mode control method of the present invention is proposed. Considering the tradeoff between the capacity and the communication quality, the control method can adaptively manage the compressed mode operation based on the potential impacts on the capacity and the effectiveness of the compressed mode measurement. The present invention will improve the effectiveness and performance of the compressed mode operation.Item type:Item, Optical element apparatus for two-dimensional controllable localized partition backlight module(2010-09-14) ;Tien ;Chung-Hao ;Lu ;Yen-HsingChengThe optical element apparatus for two-dimensional controllable localized partition backlight module is disclosed. The optical element apparatus comprises of a plurality of optical units which include a plurality of point light sources, light guides and collimating sheets. The point light source is located at the center of the light guide. The light guide includes the incident surface, the bottom place connecting with the light incident surface, and the light output surface. There are micro structures on the bottom place of the light guide and the top surface of the collimating sheet.Item type:Item, Synthesis and Characterization of a Thiadiazole/Benzoimidazole-Based Copolymer for Solar Cell Applications(2010-09-15) ;Chen, Guan-yu ;Lan, Shang-che ;Lin, Po-yu ;Chu, Chih-weiWei, Kung-hwaIn this study, we synthesized a new polymer, PCTDBI, containing alternating carbazole and thiadiazole-benzoimidazole (TDBI) units. This polymer (number-average molecular weight - 25,600 g mol(-1)), which features a planar imidazole structure into the polymeric main chain, possesses reasonably good thermal properties (T(g) = 105 degrees C; T(d) = 396 degrees C) and an optical band gap of 1.75 eV that matches the maximum photon flux of sunlight. Electrochemical measurements revealed an appropriate energy band offset between the polymer's lowest unoccupied molecular orbital and that of PCBM, thereby allowing efficient electron transfer between the two species. A solar cell device incorporating PCTDBI and PCBM at a blend ratio of 1: 2 (w/w) exhibited a power conversion efficiency of 1.20%; the corresponding device incorporating PCTDBI and PC(71)BM (1: 2, w/w) exhibited a PCE of 1.84%. (C) 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 4456-4464, 2010Item type:Item, Characteristics of emission polarization in a-plane nanorods embedded with InGaN/GaN multiple quantum wells(2010-09-15) ;Li, J. C. ;Lu, T. C. ;Huang, H. M. ;Chan, W. W.Kuo, H. C.Nonpolar (a-plane) GaN nanorod arrays with embedded In(x)Ga(1-x)N/GaN (x=0.09, 0.14, 0.24, and 0.30) multiple quantum wells (MQWs) grown on r-plane sapphire have been fabricated successfully by self-assembled Ni nanomasks and subsequent inductively coupled plasma reactive-ion etching. After nanorod fabrications, the polarization ratio of the emission from MQWs with lower indium composition (x=0.09 and 0.14) slightly decreases but apparently increases by at most 79% for the samples with higher indium composition (x=0.24 and 0.30). Competition between the effect of multiple scattering, strain relaxation and reduction in localized centers, expected in a-plane MQW samples, are attributed to the variations in the polarization ratios after the nanorod formation. (c) 2010 American Institute of Physics. [doi:10.1063/1.3483239]Item type:Item, Compensation effect and differential capacitance analysis of electronic energy band structure in relaxed InAs quantum dots(2010-09-15) ;Chen, J. F. ;Chen, Ross C. C. ;Chiang, C. H. ;Hsieh, M. C.Chang, Y. C.The use of a differential capacitance technique for analyzing the effect of strain relaxation on the electronic energy band structure in relaxed InAs self-assembled quantum dots (QDs) is presented. Strain relaxation is shown to induce a deep defect state and compensate the ionized impurity in the bottom GaAs layer, leading to a double depletion width and a long emission time. An expression of capacitance at different frequency and voltage is derived for analyzing the experimental data. It has been shown that the relationship between the low-frequency and high-frequency capacitances can be well explained by a Schottky depletion model with a compensated concentration in the bottom GaAs layer. A simple expression is presented to account for the modulation of the free electrons in the top GaAs layer. This capacitance analysis shows a long low-energy tail for the electron ground state, suggesting not very uniform strain relaxation. The results of this study illustrate a carrier compensation effect of the defect state on the electronic energy band structure near the QDs. (C) 2010 American Institute of Physics. [doi:10.1063/1.3467938]Item type:Item, Improvement in output power of a 460 nm InGaN light-emitting diode using staggered quantum well(2010-09-15) ;Liao, Chih-Teng ;Tsai, Miao-Chan ;Liou, Bo-Ting ;Yen, Sheng-HorngKuo, Yen-KuangStaggered quantum well structures are studied to eliminate the influence of polarization-induced electrostatic field upon the optical performance of blue InGaN light-emitting diodes (LEDs). Blue InGaN LEDs with various staggered quantum wells which vary in their indium compositions and quantum well width are theoretically studied and compared by using the APSYS simulation program. According to the simulation results, the best optical characteristic is obtained when the staggered quantum well is designed as In(0.20)Ga(0.80)N (1.4 nm)-In(0.26)Ga(0.74)N (1.6 nm) for blue LEDs. Superiority of this novelty design is on the strength of its enhanced overlap of electron and hole wave functions, uniform distribution of holes, and suppressed electron leakage in the LED device. (C) 2010 American Institute of Physics. [doi:10.1063/1.3471804]Item type:Item, Stability of nanoscale twins in copper under electric current stressing(2010-09-15) ;Chen, Kuan-Chia ;Wu, Wen-Wei ;Liao, Chien-Neng ;Chen, Lih-JuannTu, K. N.Migration of {112} incoherent twin boundary (ITB) in nanotwinned Cu under electric current stressing has been observed using in situ high-resolution transmission electron microscopy. The current-driven ITB migration is found to be four orders of magnitude faster than that driven thermally. We propose that electric current plays a role of shuffling Cu atoms at ITB/coherent twin boundary junctions, which enhances nucleation of {112} steps and facilitates twin boundary migration in Cu. By understanding how twin boundaries respond to electric current force we shall be able to trace the property change in nanotwinned Cu under electric current stressing, which would be an essential assessment of interconnect reliability. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3483949]Item type:Item, Spectrofluorometric assay for monoamine-preferring phenol sulfotransferase (SULT1A3)(2010-09-15) ;Lu, Lu-Yi ;Hsu, Yen-Chang ;Yang, Yuh-Shyong ;生物科技學系Department of Biological Science and TechnologyA continuous and real-time fluorometric assay for monoamine-preferring phenol sulfotransferase (SULT1A3) was developed. The methodology was based on the coupling of SULT1A1 to regenerate 3'-phosphoadenosine-5'-phosPhosulfate (PAPS) using 4-methylumbelliferyl sulfate (MUS) as a sulfuryl group donor. The fluorophore product (4-methylumbelliferone. MU) was continuously produced and monitored when SULT1A3 catalyzed dopamine sulfation with PAPS. The optimal conditions of this turnover reaction and substrate inhibition of SULT1A3 were also determined. This coupled-enzyme assay allows the continuous measurement of initial reaction velocity and the sensitivity is comparable to that of end-point radioactive isotope assay. (C) 2010 Elsevier Inc. All rights reserved.Item type:Item, Stability of nanoscale twins in copper under electric current stressing(2010-09-15) ;Chen, Kuan-Chia ;Wu, Wen-Wei ;Liao, Chien-Neng ;Chen, Lih-JuannTu, K. N.Migration of {112} incoherent twin boundary (ITB) in nanotwinned Cu under electric current stressing has been observed using in situ high-resolution transmission electron microscopy. The current-driven ITB migration is found to be four orders of magnitude faster than that driven thermally. We propose that electric current plays a role of shuffling Cu atoms at ITB/coherent twin boundary junctions, which enhances nucleation of {112} steps and facilitates twin boundary migration in Cu. By understanding how twin boundaries respond to electric current force we shall be able to trace the property change in nanotwinned Cu under electric current stressing, which would be an essential assessment of interconnect reliability. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3483949]Item type:Item, Characteristics of emission polarization in a-plane nanorods embedded with InGaN/GaN multiple quantum wells(2010-09-15) ;Li, J. C. ;Lu, T. C. ;Huang, H. M. ;Chan, W. W.Kuo, H. C.Nonpolar (a-plane) GaN nanorod arrays with embedded In(x)Ga(1-x)N/GaN (x=0.09, 0.14, 0.24, and 0.30) multiple quantum wells (MQWs) grown on r-plane sapphire have been fabricated successfully by self-assembled Ni nanomasks and subsequent inductively coupled plasma reactive-ion etching. After nanorod fabrications, the polarization ratio of the emission from MQWs with lower indium composition (x=0.09 and 0.14) slightly decreases but apparently increases by at most 79% for the samples with higher indium composition (x=0.24 and 0.30). Competition between the effect of multiple scattering, strain relaxation and reduction in localized centers, expected in a-plane MQW samples, are attributed to the variations in the polarization ratios after the nanorod formation. (c) 2010 American Institute of Physics. [doi:10.1063/1.3483239]Item type:Item, Synthesis and Characterization of PEG-PCL-PEG Triblock Copolymers as Carriers of Doxorubicin for the Treatment of Breast Cancer(2010-09-15) ;Cuong, Nguyen-Van ;Hsieh, Ming-Fa ;Chen, Yung-Tsung ;Liau, Ian應用化學系分子科學碩博班Triblock copolymers of monomethoxy poly(ethylene glycol) (mPEG) and epsilon-caprolactone (CL) were prepared with varying lengths of poly(E-caprolactone) (PCL) compositions and a fixed length of mPEG segment. The molecular characteristics of triblock copolymers were characterized by NMR, gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and differential scanning calorimetry (DSC). These amphiphilic linear copolymers based on PCL hydrophobic chain and hydrophilic mPEG ending, which can self-assemble into nanoscopic micelles with their hydrophobic cores, encapsulated doxorubicin (DOX) in an aqueous solution. The particle size of prepared micelles was around 40-92 nm. The DOX loading content and DOX loading efficiency were from 3.7-7.4% to 26-49%, respectively. DOX-released profile was pH-dependent and faster at pH 5.4 than pH 7.4. Additionally, the cytotoxicity of DOX-loaded micelles was found to be similar with free DOX in drug-resistant cells (MCF-7/adr). The great amounts of DOX and fast uptake accumulated into the MCF-7/adr cells from DOX-loaded micelles suggest a potential application in cancer chemotherapy. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 117: 3694-3703, 2010Item type:Item, CONTROL METHOD OF TRANSMITTING STREAMING AUDIO/VIDEO DATA AND ARCHITECTURE THEREOF(2010-09-16) ;HUANG, Ching-Yao ;CHEN, Zhi-ZhanLI, Chun-HsiaoA control method and architecture for controlling transmission of streaming audio/video data are disclosed. The method uses a report transmission rate on a transmitter to reduce the playback latency on a receiver. The report transmission rate is determined according to an actual transmission rate and the residual data amount of the previous period of a transmitter buffer. The actual transmission rate is the minimum of an available transmission rate and a required transmission rate, which depends on the residual data amount and the report transmission rate. Therefore, the report transmission rate is adjusted according to the accumulation of residual data of transmitter buffer, which improves the playback latency.Item type:Item, 定位定量黏著封裝方法與結構(2010-09-16) ;邱俊誠 ;侯冠州 ;林君穎張志瑋有鑑於習知流體自組裝技術利用親疏水性材料來輔助微小元件定位,本發明提出一種定位定量黏著封裝方法與結構,也就是先將液態膠定位方法,本發明先將第一基板劃分出親水性區域與疏水性區域,點上液態膠於第一基板親水區域上,再利用第二基板靠近第一基板,先保留一間隙於兩基板間,使液態膠藉由毛細現象之吸引力流動分佈於親水性區域,最後,選擇是否將第二基板移開或接合第一基板,若選擇後者,可將第二基板做微流道或置容孔之設計,以有助於後段製程時微小晶粒之定位,並且可防止溢膠的情況產生。Item type:Item, 單電感多輸出電源轉換器及其控制方法(2010-09-16) ;陳科宏黃銘信一種單電感多輸出電源轉換器及其控制方法,包括一電感具有第一端及第二端,該電感的第一端連接該電源轉換器的輸入端,該電感的第二端在該電源轉換器的多個輸出端、該電源轉換器的輸入端及一接地端之間做切換。Item type:Item, Using decision rules to achieve mass customization of airline services(2010-09-16) ;Liou, James J. H. ;Yen, Leon ;Tzeng, Gwo-Hshiung ;科技管理研究所Institute of Management of TechnologyThis paper uses the Dominance-based Rough Set Approach (DRSA) to formulate airline service strategies by generating decision rules that model passenger preference for airline service quality. DRSA could help airlines eliminate some services associated with dispensable attributes without affecting passenger perception of service quality. DRSA could also help airlines achieve mass customization of airline services and generate additional revenues by active or passive targeting of quality services to passengers. (C) 2009 Published by Elsevier B.V.Item type:Item, 升降壓電源轉換器及其控制方法以及應用在該升降壓電源轉換器的鋸齒波產生器及其方法(2010-09-16) ;陳科宏 ;黃柄境何心欣一種升降壓電源轉換器包括一功率級用以將一輸入電壓轉為一輸出電壓,一誤差放大器根據一與該輸出電壓具有比例關係的回授信號及一參考電壓產生一誤差信號,一鋸齒波產生器提供兩組鋸齒波信號,以及兩組比較器根據該誤差信號及該兩組鋸齒波信號產生兩組控制信號用以驅動該功率級。該兩組鋸齒波信號其中之一的峰値隨該輸入電壓改變,另一組鋸齒波信號的谷値隨該輸入電壓改變,因而可以加快線性暫態響應,避免因該輸入電壓變化而造成該輸出電壓的不穩定。Item type:Item, 升降壓式電源轉換器及其控制方法(2010-09-16) ;陳科宏 ;吳緯權何心欣一種升降壓式電源轉換器及其控制方法,其在該電源轉換器的輸入電壓接近輸出電壓時延長開關的切換週期並使用新的開關順序來改善切換損失及導通損失,並且考慮負載電流對責任週期的影響使其可在正確點切換模式,因此該輸出電壓不會因為改變模式而受影響。