Browsing by Issue Date, starting with "2017-11-01"

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Flow field investigation in a rotating disk chemical vapor deposition chamber with a perforated showerhead
(2017-11-01)
Liu, Yao-Hsien
;
Peng, Guan-Jhong
;
Lai, Wei-Chia
;
Huang, Chih-Yung
;
Liang, Jin-Hsing
A flow field in a simulated rotating disk chemical vapor deposition chamber in which the inflow gases entered through a showerhead inlet was experimentally investigated using particle image velocimetry. The deposition uniformity was highly related to the flow pattern, which was influenced by the buoyancy, centrifugal, and flow inertia forces. This study investigated flow patterns for different processing parameters, namely chamber heights (20 and 40 mm), jet-to-disk temperature differences (0-500 degrees C), and disk rotational speeds (0-500 rpm). The time-averaged axial and radial velocity profiles were determined for examining the effects of rotation and heating on flow uniformity above the rotating disk. The Reynolds stress and turbulence intensity was found to be influenced by the buoyancy and rotation induced flow. At a high jet-to-disk temperature difference, the upward buoyancy force lifted the flow and prevented the inlet flow from reaching the disk surface. The buoyancy-induced flow can be suppressed through disk rotation or chamber height reduction. Moreover, the nondimensional parameters (Grashof number and rotational Reynolds number) can be used to construct flow regime maps and quantify the effects of rotation and heating even with the contribution from different chamber heights, disk temperatures, and rotational speeds. (C) 2017 Elsevier Inc. All rights reserved.
Channel-Aware Resource Allocation for Energy-Efficient Cloud Radio Access Networks Under Outage Specifications
(2017-11-01)
Li, Pei-Rong
;
Feng, Kai-Ten
;
電機工程學系
;
Department of Electrical and Computer Engineering
This paper investigates a cloud radio access network (C-RAN) architecture for future wireless network, which focuses on centralized processing for spatially distributed remote radio heads (RRHs). Our main goal is to promote an energy efficient C-RAN under the consideration of multiple access interference (MAI) and imperfect channel state information at the transmitter (CSIT) via outage-aware resource allocation. The closed-form expression of fading-induced outage probability for each transceiver pair will be established by analyzing the statistical property of signal-to-interference-plus-noise. In the course of finding feasible solutions to enhance energy efficiency, the optimization procedures named C-RAN-based energy efficient power allocation (CEEPA) and low-complexity CEEPA are proposed. As the number of RRHs grows to infinity, the deterministic equivalents of performance metrics can be derived by applying recent results from random matrix theorem, which lead to an efficient way to obtain the asymptotic-optimal resource allocation policy. Also, the regularized zero-forcing precoding technique is adopted to mitigate MAI and can tackle the impact of imperfect CSIT thanks to the derivation of deterministic equivalents. Numerical simulations show that the proposed resource allocation schemes can provide better energy efficiency and the accuracy of asymptotic expressions is also verified. Furthermore, the merit of a distributed antenna system is demonstrated through the comparison with centralized antenna system.
場效電晶體結構
(2017-11-01)
張俊彥
一種場效電晶體結構，包括：基底、內部閘極、絕緣層、半導體帶、閘介電絕緣結構以及閘導體結構。內部閘極包括位於基底上的層狀部以及自層狀部延伸的牆部。絕緣層位於內部閘極的層狀部上。半導體帶位於牆部與部分絕緣層上，其中半導體帶包括源極/汲極區以及與源極/汲極區相鄰的通道區。閘介電絕緣結構位於通道區上。閘導體結構位於閘介電絕緣結構上。
Presymptomatic Diagnosis of Spinal Muscular Atrophy Through Newborn Screening
(2017-11-01)
Chien, Yin-Hsiu
;
Chiang, Shu-Chuan
;
Weng, Wen-Chin
;
Lee, Ni-Chung
;
Lin, Ching-Jie
Objective To demonstrate the feasibility of presymptomatic diagnosis of spinal muscular atrophy (SMA) through newborn screening (NBS). Study design We performed a screening trial to assess all newborns who underwent routine newborn metabolic screening at the National Taiwan University Hospital newborn screening center between November 2014 and September 2016. A real-time polymerase chain reaction (RT-PCR) genotyping assay for the SMN1/SMN2 intron 7 c. 888+100A/G polymorphism was performed to detect homozygous SMN1 deletion using dried blood spot (DBS) samples. Then the exon 7 c. 840C>T mutation and SMN2 copy number were determined by both droplet digital PCR (ddPCR) using the original screening DBS and multiplex ligation-dependent probe amplification (MLPA) using a whole blood sample. Results Of the 120 267 newborns, 15 tested positive according to the RT-PCR assay. The DBS ddPCR assay excluded 8 false-positives, and the other 7 patients were confirmed by the MLPA assay. Inclusion of the second-tier DBS ddPCR screening assay resulted in a positive prediction value of 100%. The incidence of SMA was 1 in 17 181 (95% CI, 1 in 8323 to 1 in 35 468). Two of the 3 patients with 2 copies of SMN2 and all 4 patients with 3 or 4 copies of SMN2 were asymptomatic at the time of diagnosis. Five of the 8 false-positives were caused by intragenic recombination between SMN1 and SMN2. Conclusion Newborn screening can detect patients affected by SMA before symptom onset and enable early therapeutic intervention. A combination of a RT-PCR and a second-tier ddPCR can accurately diagnose SMA from DBS samples with no false-positives.
Mode-locking S-band erbium fiber laser by employing alcohol-based saturable-absorber
(2017-11-01)
Hsu, Yung
;
Yeh, Chien-Hung
;
Chow, Chi-Wai
;
光電工程學系
;
Department of Photonics
In this work, we investigate a passively mode-locked erbium-doped fiber (EDF) laser employing alcohol-based saturable absorber (SA) in S-band window for the first time. The operated S-band range is completed by using erbium-doped silica fiber with depressed cladding scheme and 980 nm pump laser to produce the gain extension effect in S-band. The alcohol is utilized to serve as the saturable absorber (SA) of the EDF laser, which is cost-effective and easily-prepared. Here, the pulse repetition rate and pulse duration of proposed EDF laser are 2.55 MHz and 13.2 ns, respectively, when the 980 nm pump laser is set at 455 mW. In addition, to the best of our knowledge, it is the first investigation of passively mode-locked EDF laser with an alcohol-based SA in S-band.
2-V operated flexible vertical organic transistor with good air stability and bias stress reliability
(2017-11-01)
Huang, Kuan-Min
;
Lin, Hung-Cheng
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Kawashima, Kazuaki
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Osaka, Itaru
;
Zan, Hsiao-Wen
In this work, we demonstrated a vertical organic transistor using air-stable material to exhibit good lifetime, good bias-stress reliability, and low operation voltage on a flexible plastic substrate in air ambient. With a synthesized NTz-based semiconducting polymer, the proposed space-charge-limited transistor (SCLT) delivers high on-off current ratio of 160000 and high output current density of 10 mA/cm(2) at about 2 V. Without encapsulation, the proposed transistor keeps stable current-voltage relationship for 180 days and has only 0.1 V threshold voltage shift after 5000 s bias stress. No significant degradation can be observed after 1000-times bending and a maximum gain of 14 can be obtained when connecting the flexible transistor with a resistor to form an inverter. (C) 2017 Elsevier B.V. All rights reserved.
Order Aggressiveness, Trading Patience, and Trader Types in a Limit Order Market
(2017-11-01)
Chiu, Junmao
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Chung, Huimin
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Wang, George H. K.
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資訊管理與財務金融系註：原資管所+財金所
;
Department of Information Management and Finance
This study examines the order aggressiveness and trading patience of foreign institutional traders, futures proprietary firm traders, individual day and non-day traders in the Taiwan index futures market. We consider order choice given a completely transparent limit order book. Our empirical results show that individual (foreign institutional) traders use a more aggressive (patient) order submission strategy than the other trader types. We find significant differences among trader types in the timing of order aggressiveness and trading patience over the intraday time period. Both top and rest-of-the-order-book activities affect traders' order submission decisions. (c) 2016 Wiley Periodicals, Inc. Jrl Fut Mark 37:1094-1123, 2017
High-resolution and compact virtual mouse using lens arrays to capture finger images on light sensors
(2017-11-01)
Qin, Zong
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Chang, Yu-Cheng
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Su, Yu-Jie
;
Huang, Yi-Pai
;
Shieh, Han-Ping D.
To realize a finger positioning device, as called "virtual mouse," to replace a touchpad, touchscreen, or even real mouse, current positioning technologies cannot achieve a sufficient resolution, a compact volume, and a simple detection algorithm simultaneously. For this problem, using a light-emitting diode source, two lens arrays, and two light sensors, we design and implement a virtual mouse prototype. The optical architecture is carefully determined for a compact volume, a sufficient resolution, and a high detection accuracy. Corresponding to a compact system volume of 3.1 mm (thickness) x 4.5 mm (length) x 2, a theoretical resolution higher than 25 pixels per inch (ppi) can be obtained over a working area of 10 cm x 10 cm. Experiments are also implemented, in which a mean detection error of 0.24 cm that corresponds to approximately two distinguishable points, and a minimal resolution of 26 ppi over the whole working area are verified. If the system thickness is relaxed to 25 mm, a resolution higher than 200 ppi can be achieved. The proposed virtual mouse, which is simple enough and potential to be extended for three-dimensional position detection, can be integrated with a flat panel display to achieve a compact display application that can interact with users.
Effects of freshwater clam extract on fracture induced inflammation at early stage
(2017-11-01)
Yeh, Kuang-Ting
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Wu, Wen-Tien
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Subeq, Yi-Maun
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Niu, Chi-Chien
;
Liao, Kuang-Wen
The inflammatory process after traumatic fracture and soft tissue injury includes release of inflammatory cytokines and activated polymorph nuclear cells (PMN) that can cause subsequent affected limbs delayed healing and vital organ complications. Analgesics have good effect on relief of the symptom but may cause further burden for hepatic and renal metabolism. Freshwater clam extract (FCE) has been demonstrated to suppress the release of the pro-inflammatory cytokine tumor necrosis factor-alpha production after hemorrhagic shock, and decrease the level of liver injury marker in rats. The aim of the present study was to determine whether FCE is able to affect the inflammation induced by unilateral tibial fracture in a rat model. The rats were randomly divided into control, fracture, FCE and fracture with FCE groups. The fracture group received left tibia and fibula shaft fractures using a consistent three point bending method. For the fracture with FCE group, FCE (40 mg/kg) was administered orally after fracture. Their physiological changes were continuously monitored for 48 h. Blood samples were extracted from the femoral arterial catheter at 1, 3, 6, 9, 12, 18, 24 and 48 h after fracture. In comparison with fracture group, those whom were fed with FCE had more stable heart rate frequency, lower central temperature at the initial h, and lower serum level of the proinflammatory cytokines and muscle damage markers induced by fracture. FCE was also associated with decreased recruitment of inflammatory cells in the adjacent soft tissue. Thus, the present results suggest that FCE could decrease fracture induced inflammation reaction and have beneficial regulatory effect on post inflammatory response.
Wavelength-selectable and steady single-mode erbium-doped fiber multiple ring laser
(2017-11-01)
Yeh, Chien-Hung
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Yang, Zi-Qing
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Huang, Tzu-Jung
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Chow, Chi-Wai
;
Chen, Jing-Heng
To achieve a stable and selectable C-band erbium-doped fiber (EDF) laser with single-longitudinal-mode output, a multiple ring architecture is proposed and demonstrated experimentally. In this work, we design a passively quadruple-ring structure in the cavity of an EDF laser to produce a Vernier effect with a mode filter for suppressing the multimode spikes significantly. In addition, the output performance and stability of the proposed EDF ring laser are discussed.
Role of rifampin for the treatment of bacterial infections other than mycobacteriosis
(2017-11-01)
Lee, Chun-Yuan
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Huang, Chung-Hao
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Lu, Po-Liang
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Ko, Wen-Chien
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Chen, Yen-Hsu
Objectives: Rifampin was initially approved for the treatment of tuberculosis. Because of its low toxicity, broad-spectrum activity, and good bioavailability, rifampin is now commonly administered as combination antimicrobial therapy for the treatment of various infections caused by organisms other than mycobacteria. This review summarizes the most recent clinical studies on the use of rifampin combinations for treating four common non-mycobacterial infections: acute bacterial meningitis, infective endocarditis and bacteraemia, pneumonia, and biofilm-related infections. Methods: We performed a literature search of clinical studies published in English from January 2005 to June 2016 using the PubMed database with the search terms "rifampin" with "meningitis" or "infective endocarditis and bacteraemia" or "pneumonia" or "prosthetic joint infections. Results: Current evidence to support a rifampin combination therapy as a treatment for non-mycobacterial infections was largely based on in vitro/in vivo studies and non-comparable retrospective case series. Additionally, controlled clinical trials that directly compared outcomes resulting from rifampin treatment versus treatment without rifampin were limited. Conclusions: Rifampin combination therapy appears promising for the treatment of non-mycobacterial infections. However, further definitive clinical trials are necessary to validate its use because the risk of adverse drug-drug interactions and of the emergence of rifampin resistance during treatment may outweigh the potential benefits. (C) 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.
四相移鍵控解調變器
(2017-11-01)
羅吉逸
;
洪浩喬
本發明提供一種新穎的四相移鍵控(Quadrature Phase-Shift Keying ，QPSK)解調變器，稱為蝴蝶結四相移鍵控(Bowknot Quadrature Phase-Shift Keying ，BQPSK)解調變器，其是利用一延遲電路以延遲一蝴蝶結四相移鍵控訊號，將其與未延遲的蝴蝶結四相移鍵控訊號混合，以輸出一組IQ資料訊號，同時利用一相位旋轉電路，藉由該解調正交資料訊號以解出一回復時脈。本發明之一種蝴蝶結四相移鍵控解調變器不需要類比數位轉換器、也不需要擁有正交時脈的振盪器，而擁有高資料率、低功耗、架構簡單和可靠的好處，且其於數位或類比電路皆可實施。
Highly sensitive and selective detection of mercury ions using N, S-codoped graphene quantum dots and its paper strip based sensing application in wastewater
(2017-11-01)
Nguyen Thi Ngoc Anh
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Chowdhury, Ankan Dutta
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Doong, Ruey-an
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環境工程研究所
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Institute of Environmental Engineering
The development of robust and low-cost sensing materials with superior selectivity and sensitivity for rapid detection of analytes in a wide variety of samples has attracted much attention. Herein, the N, S-codoped graphene quantum dots (N, S-GQDs) with high quantum yield were fabricated by one-pot hydrothermal method for highly sensitive and selective detection of nanomolar level of mercury ions (Hg2+) in water and wastewater. The as-prepared N, S-GQDs are uniform in size with mean particle size of 3.5 +/- 0.5 nm. The doping of nitrogen atoms increases the quantum yield to 41.9%, while the introduction of sulfur atoms enhances the selectivity of Hg2+ via strong coordination interaction. The fluorescence intensity of N, S-GQDs is quenched proportionally after adding Hg2+ and a dynamic range of 4 orders of magnitude with limit of detection of 0.14nM is obtained in deionized water. The N, S-GQDs nanosensing probes can be successfully applied to the sewage and dye wastewater samples and a linear range of 0.1-15 mu M with recovery of 96-116% is obtained. In addition, the coating of N, S-GQDs onto paper strip provides an excellently rapid screening and highly selective technique for Hg2+ detection in real wastewater. Results obtained in this study clearly indicate that the N, S-GQDs are promising nanomaterials which can open an new avenue to design the GQD based sensing probe for highly sensitive and selective detection of metal ions and other analytes in environmental and biological fluid samples. (C) 2017 Elsevier B.V. All rights reserved.
Using nanoindentation to investigate the temperature cycling of Sn-37Pb solders
(2017-11-01)
Wen, Hua-Chiang
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Chou, Wu-Ching
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Lin, Po-Chen
;
Jeng, Yeau-Ren
;
Chen, Chien-Chang
Using nanoindentation and energy dispersive X-ray spectrometry (EDS), we have conducted an investigation into corner failures to elucidate not only the nanomechanical properties of Sn-37Pb solder balls but also the effects of temperature cycling tests (TCTs). We found that the hardness of Sn-37Pb solder balls was greater in central locations [1.18 +/- 0.05 GPa for room-temperature (RT) sample; 1.3 +/- 0.05 GPa for TCT sample], but had standard values in corner locations (>0.2 +/- 0.02 GPa). The modulus increased after the TCTs. Nevertheless, the mechanical properties were closely related to the average area of the alpha-Pb phase. The average area of the Pb-rich region was more stable after the TCTs than that of the RT sample, due to the enhanced mechanical properties of the Sn-37Pb solder, suggesting good reliability. From an analysis of average areas in the RT sample, it appears that the Pb-rich solid solution that formed led to weak Sn-Pb bonds near the corner locations. Electron back scattered diffraction measurements revealed that grains with grain boundaries formed as a result of accelerated TCT cycling. We conclude that Sn-Pb recrystallization was initiated and propagated after the TCTs, followed by propagation to the interfacial region. (C) 2017 Published by Elsevier Ltd.
A new indexing motion program for optimum designs of Geneva mechanisms with curved slots
(2017-11-01)
Lin, W. Y.
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Tsai, Y. H.
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Hsiao, K. M.
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機械工程學系
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Department of Mechanical Engineering
A curved slotted Geneva mechanism can eliminate the adversely infinite angular jerks of the Geneva wheel and might reduce the peak angular acceleration of the Geneva wheel by using a proper indexing motion program. In the literature, the cycloidal, fifth-order polynomial and modified sine indexing motion programs are frequently used for curved slotted Geneva mechanisms. To achieve the better kinematic performance of the curved slotted Geneva wheel than that obtained using the above-mentioned indexing motion programs, a new indexing motion program based on the Hermite interpolating polynomial is proposed for an optimum design with the goals of minimizing the peak angular acceleration and eliminating the adversely infinite angular jerks. The domain of the indexing position function is divided into several segments. Each segment is termed an element, and both ends of each segment are termed nodes. The nodal values of the indexing position function and its derivatives are used as design variables. The position function for each element can be described using the Hermite interpolating polynomial and the design variables. The reason behind the use of the Hermite interpolating polynomial is that the design variables have the clear physical meanings. The four-level Hermite interpolating polynomial is used and two elements are sufficient to obtain the optimum results. In addition, the constraint regarding the radius of curvature of the profile of the inner slot is proposed to prevent sharp curvature of the profile of the inner slot. The findings show that there is a decline in the peak acceleration of the Geneva wheel with six curved slots for the optimum results obtained using the proposed indexing motion program by 33.4% and 24.3%, respectively, as compared with the cycloidal and modified sine indexing motion programs.
Improved Optoelectronic Performance of High-Voltage Ultraviolet Light-Emitting Diodes Through Electrode Designs
(2017-11-01)
Tien, Ching-Ho
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Kuo, Chen-Hao
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Wuu, Dong-Sing
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Horng, Ray-Hua
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電子工程學系及電子研究所
High-efficiency high-voltage ultraviolet light-emitting diodes (HV-UVLEDs) consisting of a 4 x 4 microcells array with an area of 61 mil x 33 mil were designed and fabricated via the electrode pattern and interconnect technique. Polymer material was used to fill trench with planarization, and interconnection technology was used for metal layer connection to address wiring defect issue. In comparison with the conventional lateral UV-LED (C-UVLED), which had 33.6% and 34.7% enhancement in the light output power and wall-plug efficiency (at 1.5 W) of the HV-UVLEDs. A 56% improvement in the external quantum efficiency droop behavior was achieved for the HV-UVLEDs when compared with that of C-UVLED. This improvement can be attributed to superior current spreading in the HV-UVLED due to its smaller microcells, which increases light-emission efficiency overall.
Analysis of growth kinetics and impact of NH3 on the morphology evolution of hexagonal-prism shaped Y4O(OH)(9)NO3/Y2O3 single crystals
(2017-11-01)
Ray, Sudeshna
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Nair, Govind B.
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Dhoble, S. J.
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Kato, H.
;
Kakihana, Masato
The effect of NH3 on the morphology evolution of single crystalline hexagonal-prism like Y4O(OH)(9)NO3 and Y2O3 has been systematically investigated, as a function of reaction time, by using a combination of powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). Rational control over the morphology has been achieved by the choice of suitable electrolytes like NaNO3, KNO3, NH4NO3, KCl and NH4Cl in the presence of NH4OH. We report that the cross-sectional geometry of hydrothermally grown one-dimensional Y4O(OH)(9)NO3 crystals can be tuned from spherical to hexagonal-prism like shape by introducing a particular reagent like NH4NO3 in the presence of NH4OH. An 'oriented attachment' mediated growth process takes place along with the 'dissolution-recrystallization' route which eventually resulted in the generation of the single crystals with hexagonal-prism like morphology. (C) 2017 Elsevier Ltd. All rights reserved.
民國時期新加坡大埔人與原鄉互動研究：以吳深才《帳本》和吳發祥《日記交易》為中心
(國立交通大學客家文化學院, 2017-11)
蕭文評
;
王濯巾
;
鐘敏麗
;
Wen-ping Xiao
;
Zhuo-jing Wang
本文以新加坡華僑吳深才《帳本》（1912-1948）與其父大埔人吳發祥《日記交易》為中心，探討民國時期新加坡大埔人與原鄉的互動關係。該帳本和日記除了記錄吳深才在新加坡捐資茶陽會館、茶陽勵志社等外，還詳細記錄了每年寄錢寄物回原鄉的次數和數量及水客名字，親人往來新加坡的花銷以及日程記錄，以及捐資原鄉辦學、修橋、作福等活動。對於瞭解民國時期新加坡大埔人與原鄉之間的互動，提供了一個不可多得的具體個案。
The Strategic Analysis of Driving Forces Determining Success for a Console Manufacturer in the Console Market - the Positioning Strategy of Nintendo
(2017-11-01)
Lee, S. J.
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Lin, Grace T. R.
;
Yu, W. H.
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科技管理研究所
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Institute of Management of Technology
Though the console market is steadily growing, the competition is very fierce. A variety of key factors get involved in the successful survival in the console market, including branding, cost, exclusive games, innovation, online feature, price, reliability, third parties support, technology, and timing. However, it is not easy to sustain the competitive advantages in an extremely fierce console market with other strong competitors for a long time, if there is not any change to console manufacturers. In addition to keep the original strength, Nintendo applies the most appropriate strategy to sustain its competitive advantages in the next generation.
Ferrofluid-assisted rapid and directional harvesting of marine microalgal Chlorella sp used for biodiesel production
(2017-11-01)
Ho, Shih-Hsin
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Chiu, Sheng-Yi
;
Kao, Chien-Ya
;
Chen, Tsai-Yu
;
Chang, Yu-Bin
In this work, a novel harvesting strategy using ferrofluids coupled with flocculation as a magnetic directional harvesting system was developed, providing a fast and easy way to effectively collect microalgae with no further modifications made to the ferrofluids. With a ferrofluid dosage of 25 mg L-1, a high harvesting efficiency of 95-100% was achieved within 1 min. In addition, we successfully performed a wastewater recycling strategy coupled with a microalgal ferrofluid-harvesting dynamic flow-through system to harvest biomass of Chlorella sp. MTF-7 which could achieve over 80% of the maximum level after three repeated recycling cultivations. This work demonstrated the use of an integrated microalgal ferrofluid-harvesting dynamic flow-through system to develop a simple and effective strategy to enhance microalgal harvesting efficiency, along with wastewater recycling, in a marine microalgal Chlorella sp. MTF-7. (C) 2017 Elsevier Ltd. All rights reserved.