Browsing by Issue Date, starting with "2017-07-01"

Now showing 1 - 20 of 13607

An enhanced application of Lotka-Volterra model to forecast the sales of two competing retail formats
(2017-07-01)
Hung, Hui-Chih
;
Chiu, Yu-Chih
;
Huang, Huang-Chen
;
Wu, Muh-Cherng
;
工業工程與管理學系
This research develops a sales forecasting model that can analyze the interaction effects of two retail competing formats (convenience-oriented vs. budget-oriented formats). A traditional approach to making such a forecast is based on the Lotka-Volterra equations (also called the LV-model). The LV-model assumes that the population of each species is affected by its self-growth, internal interaction within the species, and external interaction with other species. Most prior studies in business applications directly use sales data as input to the LV-model. The prior approach may result in misleading conclusions when sales data are embedded with seasonal variation, because this variation is not addressed in the original development of the LV-model. Therefore, this study proposes a forecasting framework (an enhanced application of the LV-model). The sales data of each retail format is considered as a compound data, which is decomposed into three individual components: (1) aggregate, (2) competition, and (3) seasonal components. The LV-model is used to forecast the competition component; the other two components are forecasted by typical time series methods; and the data of three components are finally combined into one. Empirical study indicates that the proposed method substantially outperforms the prior approach in terms of forecasting errors (4.4% vs. 16.7% for convenience-oriented and 5.8% vs. 16.2% for budget oriented). In addition, the proposed method reveals a more convincing predator-prey relationship between the two retail formats, which concludes that the convenience-oriented is the predator. To the opposite, the prior approach, concluding that the budget-oriented is the predator, is quite doubtful because the convenience-oriented shall be preferred while the GDP grows over time. This research makes a contribution in how to appropriately apply the LV-model in forecasting revenue and analyzing the interaction effects of two competing business species. (C) 2017 Elsevier Ltd. All rights reserved.
A Wi-Fi Union Mechanism for Internet Advertising Reciprocal Platform in Microenterprises
(2017-07-01)
Thi Thanh An Nguyen
;
Chang, Che-Pin
;
Yuan, Shyan-Ming
;
資訊工程學系
;
電機學院碩士在職專班
With the evolution of the Internet and smartphone devices, Internet advertising has become one of the most important methods for delivering promotional marketing messages to customers. However, the efficiency of Internet advertising for microenterprise is not very high, since Wi-Fi advertisingwhich is limited by a small router coverage areais mainly used. Moreover, because of the lack of money, microenterprises have been using low-cost methods to promote their products. Thus, enhancing the effectiveness of Wi-Fi advertising, and solving the problem of cost and the range of the views are now an essential investigation in this study. In this paper, we propose a reciprocal model with Wi-Fi union mechanism for Internet advertising based on fog computing architecture to enhance the efficiency of advertisement, reduce the cost, and increase the range of the views for microenterprise by using the Internet. In particular, the system was built in advertisers', publishers', and consumers' sides. In our system, we use contribution point (CP) as an exchange value among the participants. Advertisers and publishers can get CP by helping the others in the system to promote their advertisements, increasing their CP by one unit. Similarly, advertisers and publishers can use their CP to ask for assistance from the others, decreasing their CP by one unit. The result shows that the system in a Wi-Fi union is easy to use, and advertisements can be seen by all customers who are using free Wi-Fi from the stores of the union. This method can solve the problem of cost and fixed consumer groups.
Synthesis and nonlinear optical properties of push-pull type stilbene and pyrazoline based chromophores
(2017-07-01)
Szukalski, A.
;
Parafiniuk, K.
;
Haupa, K.
;
Goldeman, W.
;
Sahraoui, B.
In this work we present the synthesis, spectroscopic and nonlinear optical properties of push-pull type organic dyes based on 1-phenyl-2-pyrazoline or 4-(dimethylamino)phenyl chromophores as a donor part, and bridged by a double bound ortho- or meta-substituted nitrophenyl group as an acceptor. For the optical measurements we have used the poly(methyl methacrylate) based thin films doped with the dyes. Third harmonic generation measurements were performed under the picosecond laser regime with excitation wavelength at 1064 nm. The experimental results confirmed that investigated systems can be used as the efficient nonlinear optical systems for harmonic of light generation (tripled but also doubled frequency). It has also been proved the strong dependence between chemical structure (position of electron-acceptor moiety as well as the type of electron-donor unit) and nonlinear optical (NLO) response coming from series of isomers and derivatives. (C) 2017 Elsevier Ltd. All rights reserved.
Polymer solar cells based low bandgap A1-D-A2-D terpolymer based on fluorinated thiadiazoloquinoxaline and benzothiadiazole acceptors with energy loss less than 0.5 eV
(2017-07-01)
Keshtov, M. L.
;
Kuklin, S. A.
;
Khokhlov, A. R.
;
Osipov, S. N.
;
Radychev, N. A.
We synthesized an ultra low bandgap terpolymer denoted as P containing fluorinated-fluorene attached thiadiazoloquinoxaline and benzothiadiazole acceptors and thiophene as donor in its backbone and investigated its optical and electrochemical properties. This terpolymer is used for as donor along with PC71BM as electron acceptor in solution processed polymer solar cells (PSCs). The P showed a shows strong absorption band from 650 nm to 1100 nm with an optical bandgap of 1.12 eV and highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of -5.25 eV and -3.87 eV, respectively. After the optimization of P to PC71BM weight ratio, the optimized weight ratio 1: 2 in chlorobenzene (CB) solution, the PSC showed overall power conversion efficiency of 4.10% (J(sc) of 10.96 mA/cm(2), V-oc of 0.68 V and FF of 0.55). After the solvent additive (3 v% DIO) followed by subsequent thermal annealing (SA-TA) the PCE has been increased up to 7.54% with Jsc of 16.12 mA/cm(2), Voc of 0.65 V and FF of 0.72. The increase in the PCE is related with the enhancement in the both Jsc and FF, attributed optimized nanoscale morphology of the active layer for both efficient exciton dissociation and charge transport towards the electrodes and balanced charge transport in the device, induced by the TSA treatment of the active layer. This is the highest PCE of PSCs with an energy loss about 0.47 eV with the low bandgap of 1.12 eV. (C) 2017 Elsevier B.V. All rights reserved.
Analysis of the Short-Term Response in the Drain Current of a-IGZO TFT to Light Pulses
(2017-07-01)
Liu, H. -W.
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Chan, P. -C.
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Lin, J. -H.
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Chang, C. -Y.
;
Tai, Y. -H.
In this letter, the response in the drain current (I-D) of the amorphous indium-gallium-zinc oxide thin-film transistors under positive-bias illumination stress is measured with respect to time in less than 5 s under light pulseswith altering frequencies and duty ratios. The curves of I-D under the light pulses are affected by the different defect-reacting rates under illumination and in the dark. By taking the derivative of ID, the trend of the change in the number of defects becomes clear. The total behavior of I-D in response to light pulses can be fairly predicted by the integral of the derivative terms with a correction factor of charge trapping.
Skin sympathetic nerve activity precedes the onset and termination of paroxysmal atrial tachycardia and fibrillation
(2017-07-01)
Uradu, Andrea
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Wan, Juyi
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Doytchinova, Anisiia
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Wright, Keith C.
;
Lin, Andrew Y. T.
BACKGROUND Skin sympathetic nerve activity (SKNA) is useful for estimating sympathetic tone in humans. OBJECTIVE The purpose of this study was to test the hypotheses that (1) increased SKNA is associated with the onset and termination of paroxysmal atrial tachycardia (AT) and atrial fibrillation (AF) and (2) sinoatrial node response to SKNA is reduced in patients with more frequent AT or AF episodes. METHODS SKNA and electrocardiogram were recorded in 11 patients (4 men and 7 women; average age 66 +/- 10 years), including 3 patients with AT (11 +/- 18 episodes per patient) and 8 patients with AF (24 +/- 26 episodes per patient). RESULTS The average SKNA (aSKNA) 10 seconds before AT onset was 1.07 +/- 0.10 mu V and 10 seconds after termination was 1.27 6 0.10 mV; both were significantly (P = .032 and P < .0001) higher than that during sinus rhythm (0.97 +/- 0.09 mu V). The aSKNA 10 seconds before AF onset was 1.34 +/- 0.07 mu V and 10 seconds after termination was 1.31 +/- 0.07 mu V; both were significantly (P < .0001) higher than that during sinus rhythm (1.04 +/- 0.07 mu V). The aSKNA before onset (P < .0001) and after termination (P < .0011) was higher in AF than in AT. The sinus rate correlated (P < .0001) with aSKNA in each patient (average r = 0.74; 95% confidence interval 0.65-0.84). The r value in each patient negatively correlated with the number of AT and AF episodes (r = -0.6493; 95% confidence interval -0.8990 to -0.08073; P = .0306). CONCLUSION Increased SKNA was observed both at the onset and termination of AT and AF. Patients with more frequent AT and AF episodes had a weak correlation between sinus rate and aSKNA, suggesting sinoatrial node remodeling by tachycardia.
A 0.5-V 28-nm 256-kb Mini-Array Based 6T SRAM With Vtrip-Tracking Write-Assist
(2017-07-01)
Wu, Shang-Lin
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Li, Kuang-Yu
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Huang, Po-Tsang
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Hwang, Wei
;
Tu, Ming-Hsien
This paper presents a 28-nm 256-kb 6T static random access memory operating down to near-threshold regime. The cell array is built on foundry 4-by-2 mini-array with split single-ended large signal sensing to enable an ultra-short local bit-line of 4-b length to improve variation tolerance and performance, and to reduce disturb while maintaining manufacturability. The design employs threshold power gating to facilitate lower NAP (Sleep) mode voltage/power and faster wake-up for the cell array, and low-swing global read bit-line (GRBL) with integrated low-swing voltage precharger to improve read performance and reduce the dynamic read power. A cell Vtrip-tracking write-assist (VTWA) lowers the selected sub-array supply to cell inverter trip voltage to enhance write-ability while providing PVT tracking capability to ensure adequate data retention margin for unselected cells in the selected sub-array. The 256-kb test chip is implemented in UMC 28-nm high-kappa metal-gate (H kappa MG) CMOS technology with macro area of 1058.22 x 374.76 mu m(2). Error-free full functionality is achieved from 0.9 down to 0.5 V (limited by read VMIN) without redundancy. The low-swing GRBL reduces dynamic power by 6.5% (8.0%) at 0.9 V (0.6 V). The VTWA improves the write VMIN by 75 mV (from 0.525 to 0.45 V). The measured maximum operation frequency is 735 MHz (20 MHz) at 0.9 V (0.5 V), TT corner, 25(omicron).
High glucose enhances cAMP level and extracellular signal-regulated kinase phosphorylation in Chinese hamster ovary cell: Usage of Br-cAMP in foreign protein beta-galactosidase expression
(2017-07-01)
Lin, Hsiao-Hsien
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Lee, Tsung-Yih
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Liu, Ting-Wei
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Tseng, Ching-Ping
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生物科技學系
Glucose is a carbon source for Chinese hamster ovary (CHO) cell growth, while low growth rate is considered to enhance the production of recombinant proteins. The present study reveals that glucose concentrations higher than 1 g/L reduce the growth rate and substantially increase in cAMP (similar to 300%) at a high glucose concentration (10 g/L). High glucose also enhances the phosphorylation of extracellular signal-regulated kinase (ERK) and p27(kiP) by Western blot analysis. To determine whether the phosphorylation of ERK is involved in the mechanism, a cyclic-AMP dependent protein kinase A (PICA) inhibitor (H-8) or MEK (MAPKK) inhibitor (PD98059) was added to block ERK phosphorylation. We show that both the high glucose-induced ERIC phosphorylation and growth rate return to baseline levels. These results suggest that the cAMP/PKA and MAP signaling pathways are involved in the above mentioned mechanism. Interestingly, the direct addition of 8-bromo-cAMP (Br-cAMP), a membrane-permeable cAMP analog, can mimic the similar effects produced by high glucose. Subsequently Br-cAMP could induce beta-galactosidase (beta-Gal) recombinant protein expression by 1.6-fold. Furthermore, Br-cAMP can additionally enhance the (beta-Gal production (from 2.8- to 4.5 fold) when CHO cells were stimulated with glycerol, thymidine, dimethyl sulfoxide, pentanoic acid, or sodium butyrate. Thus, Br-cAMP may be used as an alternative agent in promoting foreign protein expression for CHO cells. (C) 2017, The Society for Biotechnology, Japan. All rights reserved.
串流服務系統、串流服務方法以及串流服務控制裝置
(2017-07-01)
許名宏
;
曾建超
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詹珉誠
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顧興亮
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周明澔
本發明提供一種串流服務系統、串流服務方法及其控制器。串流服務系統包括多個交換節點、多個代理緩存伺服器、內容管理裝置以及控制器。交換節點間相互連接，而代理緩存伺服器分別連接至交換節點之一。控制器連接至此些交換節點並與內容管理裝置進行通訊。內容管理裝置提供代理緩存伺服器的伺服器資訊至控制器。第一客戶裝置加入播放群組時，內容管理裝置通知控制器，控制器由代理緩存伺服器中選擇第一代理緩存伺服器，並且設定至少部分的交換節點以調整群播樹(Multicast Tree)。第一代理緩存伺服器由群播樹的第一傳輸路徑傳輸串流封包至第一客戶裝置。
The body mechanical: Building a caring community, crafting a functioning body
(2017-07-01)
Hung, Yiling
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通識教育中心
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Center of General Education
When Hansen's disease became treatable in Taiwan in the mid-20th century, a group of Hansen's disease patients lost their sick role despite still having lingering symptoms that continued to evolve. While sociologists have explored in-depth situations in which the social role of the sick is ambiguous, few studies have investigated body experiences under liminality that requires sick people to find a new sick role. Living with lingering symptoms in a post-Hansen's disease world, the Hansen's disease patients I have studied face the conundrum of having to find an alternative sick role. Ethnographic fieldwork demonstrates how patients develop a specific set of body techniques that shape and are shaped by their membership in a patient community. Exploring the reinforcing projects of re-embodiment and sociality around Hansen's disease, I argue that patients are able both to legitimate each other's feelings of sickness and to use those feelings to manage their illness and, as such, to collectively acquire an alternative sick role. Adding to existing discussions of active patients, this article identifies the body mechanical as a way of practicing active patienthood organized around fixing, trials, mending and functionality.
SH stretching vibration of propanethiol ice-a signature for its identification in the interstellar icy mantles
(2017-07-01)
Pavithraa, S.
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Sahu, D.
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Seth, G.
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Lo, J. -I.
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Sekhar, B. N. Raja
Among the most commonly existing thiol molecules, methanethiol and ethanethiol were discovered in the interstellar medium and identification of the next larger thiol molecule, propanethiol, is long awaited. By simulating icy astrochemical conditions and probing propanethiol ices under infrared spectroscopy we propose the use of SH stretching vibrations observed in the propanethiol molecular ice as a probe towards its identification in the interstellar medium. Though there are conformational changes within the ice (as observed in both VUV and IR spectra), the SH stretching vibration of propanethiol is observed to be unique among the set of thiol molecules, methanethiol and ethanethiol, which enables the detection of propanethiol ice in interstellar dust mantles using the James Webb Space Telescope.
Determining an Optimal Action Portfolio for Water Resource Management by Using Stochastic Programming
(2017-07-01)
Ho, Chih-Chao
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Pan, Chen-Che
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Chang, Liang-Cheng
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土木工程學系
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Department of Civil Engineering
A regional water management system always contains long-term and short-term actions in practice. The uncertainty of short-term actions increases great complexity for evaluating the performance of action portfolio comprised with long-term and short-term actions. Developing an efficient methodology to define a cost-effective action portfolio is an important task. Hence, this study develops a novel decision model, the Stochastic Programming with Recourse Decision Model (SPRDM), to compute a cost-effective action portfolio. The effectiveness of SPRDM is verified by address a problem of water shortage and financial cost in Taoyuan City, Northern Taiwan. The results shown adding Kaotai Reservoir alone can fulfill the Taoyuan demand most of the time, and the remaining extreme water shortage events can be addressed by short-term and irrigation management actions additionally. When drought duration of water shortage event is longer than 200 days, using irrigation management action to address water deficit has lower expected costs than other short-term actions do. Although the study focuses on Northern Taiwan, the proposed model is applicable to other areas with an integrated water resources management framework.
Biomass burning tracers in rural and urban ultrafine particles in Xi'an, China
(2017-07-01)
Zhu, Chong-Shu
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Cao, Jun-Ji
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Tsai, Chuen-Jinn
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Zhang, Zhi-Sheng
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Tao, Jun
To investigate the impact of biomass burning emissions on ultrafine particles (PM0.133: particulate matter with an aerodynamic diameter less than 0.133 mu m), biomass burning tracers (including levoglucosan, mannonsan and K+) were measured at a rural and an urban sites in Xi'an during winter heating period. The average levoglucosan concentrations of rural and urban PM0.133 were 0.93 +/- 0.32 mu g m(-3) and 0.29 +/- 0.14 mg m(-3), respectively. Comparable PM0.133 mannosan concentrations were observed in rural samples (0.16 +/- 0.26 mu g m(-3)) and urban samples (0.17 +/- 0.10 mu g m(-3)). Higher correlation between levoglucosan and K+ was obtained for urban samples (R = 0.86) than that for rural samples (R = 0.72). The levoglucosan to K+ ratio was found to be higher for rural samples (0.77 +/- 0.39) compared to that for urban samples (0.32 +/- 0.14). Levoglucosan to mannosan ratios averaged 7.86 and 2.83 for rural and urban samples, respectively. It can be concluded that the major source of rural biomass burning was the combustion of crop residuals and softwood. The contributions of biomass burning to OC ranged from 19% to 32%, with an average of 24% for rural samples. The results provide a better understanding on the rural and urban magnitude of levoglucosan and contributions of biomass burning in Xi'an. (C) 2017 Turkish National Committee for Air Pollution Research and Control. Production and hosting by Elsevier B.V. All rights reserved.
A General Structure of Linear-Phase FIR Filters With Derivative Constraints
(2017-07-01)
Yu, Bo-You
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Wang, Peng-Hua
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Chen, Po-Ning
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電機工程學系
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電信工程研究所
In this paper, a general structure of linear-phase finite impulse response filters, whose frequency responses satisfy given derivative constraints imposed upon an arbitrary frequency, is proposed. It is comprised of a linear combination of parallelly connected subfilters, called the cardinal filters, with weighted coefficients being the successive derivatives of the desired frequency response at the constrained frequency. An advantage of such a cardinal filters design is that only the weighted coefficients are relevant to the desired frequency response but not the cardinal filters; hence, a dynamic adjustment of the filter system becomes feasible. The key to derive the coefficients of cardinal filters is the determination of the power series expansion of certain trigonometric-related functions. By showing the elaborately chosen trigonometric-related functions satisfy specific differential equations, recursive formulas for the coefficients of cardinal filters are subsequently established, which make efficient their computations. At last, a simple enhancement of the cardinal filters design by incorporating the mean square error minimization is presented through examples.
Electronic Transport and Light Response of Air-Stable n-Type Organic Chlorophenyl-Substituted Perylene Diimide Microribbons
(2017-07-01)
Tan, Chao-Yuan
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Tseng, Pin-Yen
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Hsieh, Gen-Wen
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光電系統研究所
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照明與能源光電研究所
We report a new n-type single-crystalline microribbon based on a chlorophenyl-substituted perylene tetracarboxylic diimide derivative via solution-phase self-assembly. Electronic transport, environmental stability, and photoresponse properties of these microribbons are studied using field-effect transistors. Transistors based on a network of the as-prepared microribbons have moderate electron mobilities and ON/OFF current ratios on the order of 10(-3) cm(2)/V.s and 10(3)-10(4), respectively. The lifetime test of microribbon devices under various humidity conditions is found to be very sustainable over 100 days. Moreover, illuminating these microribbons could profoundly induce photocurrents in the visible light range, presenting good responsivity of 9.5 A/W and a high external quantum efficiency up to 2000% under 1.9 mW/cm(2). In addition, these microribbon devices are processed from solution-phase at temperatures below 100 degrees C, making the technology a viable candidate for low-cost and plastic-based organic optoelectronic applications.
企業永續成長模式探討：資源投入－雙元能力－企業績效間之動態關聯
(國立交通大學, 2017-07-01)
劉芬美
;
蔡淵輝
;
凃資芬
;
Fen-may Liou
;
Yuan-Hui Tsai
「雙元能力」強調企業必須平衡短期「應用能力」及長期「探索能力」才能維持永續成長，但對於資源投入如何建構雙元能力進而影響績效，仍待探討。企業從資源投入、能力建構、獲得績效、經檢討再回饋投資源入，這一連串動態調整的過程是企業永續經營的基礎。本研究以「資源基礎理論」及「動態能力」為基礎建構「資源投入-雙元能力-績效」之動態理論架構。在實證面，利用台灣電子產業2007-2016 年之財報資料，檢測應用能力變動與探索能力變動分別對於行銷投入變動與績效變動間、研發投入變動與績效變動間之中介影響。經實證研究結果顯示：(1)行銷資源投入變動對企業績效變動具有直接正Ｕ效果，而研發資源變動則是倒Ｕ效果。(2)行銷資源投入變動對應用能力變動具有正Ｕ效果，而研發資源變動對探索能力變動具正向影響效果。(3)探索能力變動對研發資源變動對績效變動之影響，具部分中介效果，而應用能力變動對行銷資源變動對績效變動影響之中介效果則不顯著，此結果顯示台灣電子業廠商的應用能力之建構效能有待開發，以利持續成長；另研發投入則需加強資源配置間之效率，以達到永續發展。本研究為雙元能力學說建立一個產業可用的理論架構，檢視企業長短期能力的建構狀態。
Alkali Metal Ion-enhanced Threading of a Perylenediimide-ound Polymer Chain through a Double-stranded Spiroborate Helicate with a Bisporphyrin Unit
(2017-07-01)
Ousaka, Naoki
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Yamamoto, Shinya
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Hayashi, Naoki
;
Li, Ming-Chia
;
Ho, Rong-Ming
Threading of a poly(ethylene glycol) (PEG) chain linked to a perylenediimide unit at one end with a bulky stopper at the other end through an inner cavity of a bisporphyrin-based double-stranded spiroborate helicate was remarkably accelerated in a specific solvent, in which the PEG chain enfolded sodium cations coordinating to the negatively charged spiroborate helicate, thus forming a 1: 1 inclusion complex with the perylenediimide sandwiched between the bisporphyrin unit.
Improving the Performance of ZnO Thin-Film Transistors with ZnON Source/Drain Contacts
(2017-07-01)
Kuan, Chin-I
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Lin, Horng-Chih
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Li, Pei-Wen
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
Motivation to study the ZnO channel for thin-film transistors (TFTs) is strong in light of its decent high mobility and large bandgap, enabling simultaneous coexistence of high on current and low off-state leakage. Nevertheless, the improvement in device performance for ZnO TFTs has not been fully exercised and even the field-effect mobility (mu(FE)) is degraded with downscaling the channel length owing to considerable series source/drain (S/D) resistance (R-SD). In this paper, we show that inserting a thin contact layer of ZnON between the ZnO channel and Al S/D effectively suppresses the formation of interfacial layer of AlOx and thereby reduces R-SD dramatically. This is evidenced by a significant reduction in R-SD from 30.1 to 14.4 k Omega. mu m measured on 0.5-mu m ZnO TFTs with a ZnON contact layer or not, leading to an improvement in mu(FE) from 18.2 to 29.6 cm(2)/V.s.
A new differential evolution algorithm with a combined mutation strategy for optimum synthesis of path-generating four-bar mechanisms
(2017-07-01)
Lin, W. Y.
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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 one-phase synthesis method using heuristic optimization algorithms can solve the dimensional synthesis problems of path-generating four-bar mechanisms. However, due to the difficulty of the problem itself, there is still room for improvement in solution accuracy and reliability. Therefore, in this study, a new differential evolution (DE) algorithm with a combined mutation strategy, termed the combined-mutation differential evolution (CMDE) algorithm, is proposed to improve the solution quality. In the combined mutation strategy, the DE/best/1 operator and the DE/current-to-best/1 operator are respectively executed on some superior parents and some mediocre parents, and the DE/rand/1 operator is executed on the other inferior parents. Furthermore, the individuals participating in the three mutation operators are randomly selected from the entire set of parents. The proposed CMDE algorithm with the three different search modes possesses better population diversity as well as search ability than the DE algorithm. The effectiveness of the proposed CMDE algorithm is demonstrated using five representative problems. Findings show a marked improvement in solution accuracy and reliability. The most accurate results are obtained with an approximate combination ratio for the three mutation operators.
Intercepting the Nazarov Oxyallyl Intermediate with -Formylvinyl Anion Equivalents to Access Formal Morita-Baylis-Hillman Alkylation Products
(2017-07-01)
Wu, Yen-Ku
;
Lin, Rongrong
;
West, F. G.
;
應用化學系
;
Department of Applied Chemistry
A Lewis acid catalyzed cationic domino reaction involving sequential electrocyclization and polar addition of allenol ethers onto the resulting oxyallyl species is described. The overall sequence allows a highly stereoselective synthesis of densely substituted cyclopentanoid compounds containing -formylvinyl functionality which is formally equivalent to products of a Morita-Baylis-Hillman alkylation process.