Browsing by Issue Date, starting with "2016-08-22"

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交大e-News第215期-交大研發魚肉鮮度即時感測器一分鐘即知水產鮮不鮮
(2016-08-22)
國立交通大學秘書室
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Secretariat
Physical Realization of von Neumann Lattices in Rotating Bose Gases with Dipole Interatomic Interactions
(2016-08-22)
Cheng, Szu-Cheng
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Jheng, Shih-Da
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物理研究所
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Institute of Physics
This paper reports a novel type of vortex lattice, referred to as a bubble crystal, which was discovered in rapidly rotating Bose gases with long-range interactions. Bubble crystals differ from vortex lattices which possess a single quantum flux per unit cell, while atoms in bubble crystals are clustered periodically and surrounded by vortices. No existing model is able to describe the vortex structure of bubble crystals; however, we identified a mathematical lattice, which is a subset of coherent states and exists periodically in the physical space. This lattice is called a von Neumann lattice, and when it possesses a single vortex per unit cell, it presents the same geometrical structure as an Abrikosov lattice. In this report, we extend the von Neumann lattice to one with an integral number of flux quanta per unit cell and demonstrate that von Neumann lattices well reproduce the translational properties of bubble crystals. Numerical simulations confirm that, as a generalized vortex, a von Neumann lattice can be physically realized using vortex lattices in rapidly rotating Bose gases with dipole interatomic interactions.
Color-conversion efficiency enhancement of quantum dots via selective area nano-rods light-emitting diodes
(2016-08-22)
Liu, Che-Yu
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Chen, Tzu-Pei
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Kao, Tsung Sheng
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Huang, Jhih-Kai
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Kuo, Hao-Chung
A large enhancement of color-conversion efficiency of colloidal quantum dots in light-emitting diodes (LEDs) with novel structures of nanorods embedded in microholes has been demonstrated. Via the integration of nano-imprint and photolithography technologies, nanorods structures can be fabricated at specific locations, generating functional nanostructured LEDs for high-efficiency performance. With the novel structured LED, the color-conversion efficiency of the existing quantum dots can be enhanced by up to 32.4%. The underlying mechanisms can be attributed to the enhanced light extraction and nonradiative energy transfer, characterized by conducting a series of electroluminescence and time-resolved photoluminescence measurements. This hybrid nanostructured device therefore exhibits a great potential for the application of multi-color lighting sources. (C) 2016 Optical Society of America
Effective optimization and analysis of white LED properties by using nano-honeycomb patterned phosphor film
(2016-08-22)
Lin, Huang-Yu
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Wang, Sheng-Wen
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Lin, Chien-Chung
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Tu, Zong-Yi
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Lee, Po-Tsung
This study presents an approach for patterning a polydimethylsiloxane (PDMS) phosphor film with a photonic crystal nano-honeycomb structure on a blue chip package. A phosphor film with a nano-honeycomb structure was patterned and transferred using a nanosphere and used for fabricating remote white light-emitting diodes (w-LEDs). The angular correlated color temperature deviation of the remote phosphor LED could be improved by varying nano-honeycomb structure pitches (450, 750, and 1150 nm). In particular, w-LED samples with excellent color uniformity (Delta CCT ranging from 940 to 440 K) were fabricated from 750-nm w-LED samples with nano-honeycomb-patterned tops. (C) 2016 Optical Society of America
Prorenin receptor acts as a potential molecular target for pancreatic ductal adenocarcinoma diagnosis
(2016-08-23)
Arundhathi, Arivajiagane
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Chuang, Wen-Han
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Chen, Jen-Kun
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Wang, Shin-E
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Shyr, Yi-Ming
Recent studies have implicated the prorenin receptor (PRR) is associated with pancreatic tumorigenesis. We therefore investigated the role of PRR in pancreatic tumorigenesis and assessed whether PRR can serve as a target for imaging diagnosis at early stages of PDAC. Here we show that aberrant expression of PRR in premalignant PanIN lesions, and human PDAC samples, and PDAC cell lines, particularly in Panc-1 cells. Interestingly, PRR expression was positively associated with PDAC progression. Moreover, overexpression of human PRR resulted in increased cell proliferation and decreased apoptosis, while knockdown of human PRR caused decreased cell proliferation and enhanced apoptosis in pancreatic cancer cells. We also observed that overexpression of human PRR enhanced MAPK and PI3K/Akt signaling pathways in PDAC cells, while knockdown of human PRR suppressed both of pathways. The confocal imaging analysis showed that human PRR was highly expressed in Panc-1, ASPC, and Miapaca cells, whereas BXPC-3, and HPAC cells had a significantly lower fluorescent signals. Consistently, the single-photon emission computed tomography (SPET/CT) showed that the uptake of anti-PRR labelled with I-125 was higher in Panc-1 and ASPC tumors-bearing mice after 96 hours injection. Importantly, tumors in pancreas of Pdx1-cre; LSL-Kras(G12D) mice had a significant increased PRR expression and accumulation of radioactivity at 96 h after injection. These data suggest that I-125-anti-PRR can detect the orthotopic tumors in Pdx1-cre; LSL-Kras(G12D) mice. Therefore, anti-PRR labelled with I-125 is a promising radiotracer for imaging diagnosis at early stages of pancreatic cancer.
Human heme oxygenase 1 is a potential host cell factor against dengue virus replication
(2016-08-24)
Tseng, Chin-Kai
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Lin, Chun-Kuang
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Wu, Yu-Hsuan
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Chen, Yen-Hsu
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Chen, Wei-Chun
Dengue virus (DENV) infection and replication induces oxidative stress, which further contributes to the progression and pathogenesis of the DENV infection. Modulation of host antioxidant molecules may be a useful strategy for interfering with DENV replication. In this study, we showed that induction or exogenous overexpression of heme oxygenase-1 (HO-1), an antioxidant enzyme, effectively inhibited DENV replication in DENV-infected Huh-7 cells. This antiviral effect of HO-1 was attenuated by its inhibitor tin protoporphyrin (SnPP), suggesting that HO-1 was an important cellular factor against DENV replication. Biliverdin but not carbon monoxide and ferrous ions, which are products of the HO-1 on heme, mediated the HO-1-induced anti-DENV effect by non-competitively inhibiting DENV protease, with an inhibition constant (Ki) of 8.55 +/- 0.38 mu M. Moreover, HO-1 induction or its exogenous overexpression, rescued DENV-suppressed antiviral interferon response. Moreover, we showed that HO-1 induction by cobalt protoporphyrin (CoPP) and andrographolide, a natural product, as evidenced by a significant delay in the onset of disease and mortality, and virus load in the infected mice's brains. These findings clearly revealed that a drug or therapy that induced the HO-1 signal pathway was a promising strategy for treating DENV infection.
Synergistic Combination of Multistage Magnetic Guidance and Optimized Ligand Density in Targeting a Nanoplatform for Enhanced Cancer Therapy
(2016-08-24)
Chiang, Chih-Sheng
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Shen, Yi-Shang
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Liu, Jun-Jen
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Shyu, Woei-Cherng
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Chen, San-Yuan
A new therapeutic strategy of combining multistage short-term magnetic guidance with optimized ligand-mediated targeting in a newly developed nanodelivery system is investigated to promote accumulation and modulate intratumoral distribution behavior of the nanocarriers for enhanced tumor therapy. The multifunctional magnetic nanocarriers (MNCs) composed of single-component thiol-functionalized PVA/PMA(SH) copolymer and superparamagnetic nanoparticles are developed for providing tunable dual-targeting ability and simultaneously modulating pH-responsive on/off drug release. Results show that plasma doxorubicin (Dox) concentration of the mice treated with Trastuzumab (Tra)-targeted Dox-MNCs can be rapidly decreased by applying dual-targeting treatment. More importantly, cooperative modulation of magnetic targeting and Tra density on the nanocarrier significantly optimize intratumoral distribution and enhance the utilization rate of nanomedicines within tumor to inhibit tumor growth. The mice treated with 2T-Dox-MNCs + multistage magnetic targeting (MT) (2 h d(-1)) show 7.63-fold, 3.25-fold, and 2.7-fold reduction in HER2-positive tumor volume compared to Dox-MNCs, 2T-Dox-MNCs, and 2T-Dox-MNCs + single MT (12 h). The synergistic dual-targeting approach represents a major paradigm advance in tumor treatment and nanocarrier design in preclinical application.
Bovine serum albumin detection and quantitation based on capacitance measurements of liquid crystals
(2016-08-29)
Lin, Chi-Hao
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Lee, Mon-Juan
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Lee, Wei
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影像與生醫光電研究所
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Institute of Imaging and Biomedical Photonics
Liquid crystal (LC)-based biosensing is generally limited by the lack of accurate quantitative strategies. This study exploits the unique electric capacitance properties of LCs to establish quantitative assay methods for bovine serum albumin (BSA) biomolecules. By measuring the voltage-dependent electric capacitance of LCs under an alternating-current field with increasing amplitude, positive correlations were derived between the BSA concentration and the electric capacitance parameters of LCs. This study demonstrates that quantitative analysis can be achieved in LC-based biosensing through electric capacitance measurements extensively employed in LCD research and development. Published by AIP Publishing.
A systematic approach to designing statistically powerful heteroscedastic 2 x 2 factorial studies while minimizing financial costs
(2016-08-31)
Jan, Show-Li
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Shieh, Gwowen
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管理科學系
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Department of Management Science
Background: The 2 x 2 factorial design is widely used for assessing the existence of interaction and the extent of generalizability of two factors where each factor had only two levels. Accordingly, research problems associated with the main effects and interaction effects can be analyzed with the selected linear contrasts. Methods: To correct for the potential heterogeneity of variance structure, the Welch-Satterthwaite test is commonly used as an alternative to the t test for detecting the substantive significance of a linear combination of mean effects. This study concerns the optimal allocation of group sizes for the Welch-Satterthwaite test in order to minimize the total cost while maintaining adequate power. The existing method suggests that the optimal ratio of sample sizes is proportional to the ratio of the population standard deviations divided by the square root of the ratio of the unit sampling costs. Instead, a systematic approach using optimization technique and screening search is presented to find the optimal solution. Results: Numerical assessments revealed that the current allocation scheme generally does not give the optimal solution. Alternatively, the suggested approaches to power and sample size calculations give accurate and superior results under various treatment and cost configurations. Conclusions: The proposed approach improves upon the current method in both its methodological soundness and overall performance. Supplementary algorithms are also developed to aid the usefulness and implementation of the recommended technique in planning 2 x 2 factorial designs.
Designing Self-Stabilizing Systems Using Game Theory
(2016-09)
Yen, Li-Hsing
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Huang, Jean-Yao
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Turau, Volker
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資訊工程學系
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Department of Computer Science
Self-stabilizing systems tolerate transient faults by always returning to a legitimate system state within a finite time. This goal is challenged by several system features such as arbitrary system states after faults, various process execution models, and constrained process communication means. This work designs selfstabilizing distributed algorithms from the perspective of game theory, achieving an intended system goal through private goals of processes. We propose a generic game design for identifying a maximal independent set (MIS) or a maximal weighted independent set (MWIS) among all processes in a distributed system. From the generic game several specific games can be defined which differ in whether and how neighboring players influence each other. Turning the game designs into self-stabilizing algorithms, we obtain the first algorithms for the MWIS problem and also the first self-stabilizingMIS algorithm that considers node degree (including an analysis of its performance ratio). We also show how to handle simultaneous moves of processes in some process execution models. Simulation results indicate that, for various representative network topologies, the new algorithm outperforms existing methods in terms of MIS size and convergence rate. For the MWIS problem, the new algorithms performed only slightly worse than centralized greedy counterparts.
Selective C(8)-H Activation of Imidazopyridines Mediated by Cooperative Nickel-Aluminum Catalysis
(2016-09-01)
Liu, Cheng-Yuan
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Chen, Ying-Ho
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Chen, Chih-Hao
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Yu, Ming-Shiuan
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Tsai, Fu-Yu
A catalytic paradigm is described featuring a synergistic interaction between nickel, aluminum and different ligands to impart a rather remote C-H alkenylation of imidazo[1,5-a] pyridines at the C-8 position without the necessity of installing a directing group. The scope of the direct C-H activation reactions of various 5-aryl- and 3-arylimidazopyridines is established using different sterically hindered alkynes.
Temperature-dependent electrical and dielectric properties of nematic liquid crystals doped with ferroelectric particles
(2016-09)
Hsiao, Yu-Cheng
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Huang, Sheng-Miao
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Yeh, En-Rong
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Lee, Wei
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影像與生醫光電研究所
We report on the temperature dependence of dielectric properties of nematic liquid crystals impregnated with BaTiO3 (BTO) ferroelectric nanoparticles. The behavior of ion transport at low frequencies is discussed by means of dielectric spectroscopy, which allows the ionic concentration and the relaxation time of electrode polarization to be deduced. The experimental results imply that the ferroelectric nanopartides can not only increase the traveling time of ions between two electrodes but also suppress the buildup of the electric double layers. Verified by the voltage holding ratio of cells containing various contents of BTO nanoparticles, it is obvious that doping BTO into liquid crystals is a low-cost and easy way to improve the device performance. (C) 2015 Elsevier B.V. All rights reserved.
Uncertainty Assessment of Non-normal Emission Estimates Using Non-Parametric Bootstrap Confidence Intervals
(2016-09)
Tong, L. I.
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Saminathan, R.
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Chang, C. W.
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工業工程與管理學系
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Department of Industrial Engineering and Management
Mitigating global warming problems initially involves reducing greenhouse gas (GHG) emissions, therefore the uncertainty of GHG emission estimates needs to be assessed concisely. Although the uncertainty of GHG emission estimates is generally evaluated using classical confidence interval, quantifying the uncertainty based on non-normal GHG emission estimates or small dataset may lead to a significant bias. Using bootstrap confidence intervals is an effective means of reducing such a bias. This study presents a procedure for constructing four bootstrap confidence intervals to assess the uncertainty of GHG emission estimates for three non-normal distributions (namely, Weibull, Gamma and Beta). These bootstrap confidence intervals are standard bootstrap (SB) confidence interval, percentile bootstrap (PB) confidence interval, Bias-corrected percentiles bootstrap (BCPB) confidence interval and bias-corrected and accelerated (BCa) confidence interval. The sensitivity of bootstrap intervals for emission data is examined under various combinations of sample size and parameters of underlying non-normal distributions using three indices: coverage performance, interval mean, and interval standard deviation. Simulation results indicate that the bootstrap confidence intervals for assessing the uncertainty of emission estimates are highly applicable with small sample size and the data distribution is non-normal. Compared with the classical confidence interval, bootstrap confidence intervals have smaller interval mean and smaller interval standard deviation for small sample size under non-normal distributions. This study recommends BCa confidence interval to assess the uncertainty of the emission estimates as long as sample size is 15 or more and the distribution is non-normal. A case study with emission data of the High-Bleed Pneumatic controllers demonstrates the effectiveness of the proposed procedure
Mining Health Examination Records-A Graph-Based Approach
(2016-09-01)
Chen, Ling
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Li, Xue
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Sheng, Quan Z.
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Peng, Wen-Chih
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Bennett, John
General health examination is an integral part of healthcare in many countries. Identifying the participants at risk is important for early warning and preventive intervention. The fundamental challenge of learning a classification model for risk prediction lies in the unlabeled data that constitutes the majority of the collected dataset. Particularly, the unlabeled data describes the participants in health examinations whose health conditions can vary greatly from healthy to very-ill. There is no ground truth for differentiating their states of health. In this paper, we propose a graph-based, semi-supervised learning algorithm called SHG-Health (Semi-supervised Heterogeneous Graph on Health) for risk predictions to classify a progressively developing situation with the majority of the data unlabeled. An efficient iterative algorithm is designed and the proof of convergence is given. Extensive experiments based on both real health examination datasets and synthetic datasets are performed to show the effectiveness and efficiency of our method.
An Efficient Decoder Architecture for Nonbinary LDPC Codes With Extended Min-Sum Algorithm
(2016-09)
Lin, Chia-Lung
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Tu, Shu-Wen
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Chen, Chih-Lung
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Chang, Hsie-Chia
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Lee, Chen-Yi
Nonbinary low-density-parity-check (NB-LDPC) codes, an extension of binary LDPC codes, provide stronger error-correcting capability than binary LDPC codes. However, the performance gain comes together with extraordinary increase on decoding complexity and memory requirement. Many simplification algorithms have been proposed in the literature, and the extended min-sum (EMS) algorithm is the one with minimal performance loss. In this brief, we present an efficient decoder architecture for quasi-cyclic NB-LDPC codes with the EMS algorithm. The throughput is improved by not only the double-throughput elementary check node unit but also overlapped processing for both check node and variable node units (VNUs). To reduce memory usage and computing complexity, edge-message hiding and simplified VNU are proposed as well. With these schemes, the postlayout results of a decoder for a (112, 56) NB-LDPC over GF(64) are presented. The core area occupies 2.24mm(2) and consumes 274 mW with a throughput of 124.6 Mb/s. Compared to prior NB-LDPC decoders with a similar code rate, the proposed decoder achieves better hardware efficiency and energy efficiency.
Investigating thermal conductivities of functionalized graphene and graphene/epoxy nanocomposites
(2016-09)
Wang, Tai-Yuan
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Tsai, Jia-Lin
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機械工程學系
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Department of Mechanical Engineering
This research investigated the thermal conductivities of functionalized graphene (FG) and FG/epoxy nanocomposites by using molecular dynamics simulation. The functional groups considered in FG are carboxyl and amine groups. The results indicated that the thermal conductivity of FG is markedly reduced compared with that of pristine graphene. However, the FG/epoxy nanocomposites demonstrated higher thermal conductivity than did the pristine graphene nanocomposites. To understand the enhancement mechanism, the interfacial thermal conductance (ITC) between the FG and the surrounding epoxy matrix was examined. The effects of the FG on ITC were explicated using vibrational density of state and normalized interaction energy. The improvement of the thermal conductivity of FG/epoxy nanocomposites was attributable to the enhancement of the ITC resulting from the functional groups grafted on the graphene surface. In addition, establishing the functional groups facilitates atomistic interaction between the graphene and epoxy, which can reduce the phonon mismatch and enhance the thermal transport efficiency in the nanocomposite. The enhanced thermal conductivity in the FG/epoxy nanocomposites was validated by experimental observation. (C) 2016 Elsevier B.V. All rights reserved.
Choosing the best index for the average score intraclass correlation coefficient
(2016-09)
Shieh, Gwowen
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管理科學系
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Department of Management Science
The intraclass correlation coefficient (ICC)(2) index from a one-way random effects model is widely used to describe the reliability of mean ratings in behavioral, educational, and psychological research. Despite its apparent utility, the essential property of ICC(2) as a point estimator of the average score intraclass correlation coefficient is seldom mentioned. This article considers several potential measures and compares their performance with ICC(2). Analytical derivations and numerical examinations are presented to assess the bias and mean square error of the alternative estimators. The results suggest that more advantageous indices can be recommended over ICC(2) for their theoretical implication and computational ease.
公民抗命與法治共同體：香港的可能
(國立陽明交通大學出版社, 2016-09-01)
彭麗君
自從香港在九七年回歸中國後，中國政府在年輕一代中的認受性每況愈下，而他們對香港主體的認同卻日益加強。2014年的雨傘運動，是反映香港市民反叛中國權力的最重要政治事件。本文旨在反思當中公民抗命的邏輯，尤其是主流香港社會一直視法治為其最重要的核心價值之一，究竟公民抗命和法治之間有何衝突？兩者的關係是制衡還是互構？本文會首先處理法治作為一種殖民管治的手段和邏輯，以理解法治在香港的意識形態運作，再以漢娜‧鄂蘭對法的論述作為參考，討論如何了解法律的兩面性—它既是權力的統治工具、也是人民共同意志的具體體現；它既恆久、也常變；它建立圍墻圈起法治共同體，也同時開展群體對外的關係。也因此，人民對待自己的法律，也應該學習同時質疑和尊重。
Room temperature excitonic dynamics of non-polar a-plane ZnO epifilms
(2016-09)
Lin, Ja-Hon
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Liu, Wei-Rein
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Lin, Yi-Chin
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Su, Hsing-Jung
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Chen, Hou-Ren
Pump polarization dependent carrier dynamics, particularly excitonic dynamics, of non-polar a-plane zinc oxide (ZnO) epifilms with two different thicknesses were investigated using time resolved measurements. Unlike the electron and hole dynamics through the above-bandgap excitation, transient differential reflectance (TDR) traces revealed similar trends under two orthogonal pump polarization conditions relative to the c-axis (E-pu +/- c and E-pu vertical bar vertical bar c) of a-ZnO around near-exciton-resonance excitation. By means of a band diagram, the bandgap renormalization (BGR) effect can be reasonably explained by the screening of the Coulomb potential energy due to the accumulation of relaxed free carriers that were initially excited through the absorption of two cascaded pump photons via the excitonic level, a process known as two photon absorption (TPA). Thus, the modulation depths of the TPA around zero time delay, due to simultaneous absorption of one pump and one probe photon via the excitonic level, increased linearly with the pump fluence, proportional to the modulation depth resulting from the BGR effects. (C) 2016 Author(s).
從海盜邦到耕作村：國家主權下香港的海岸與農地敘述
(國立陽明交通大學出版社, 2016-09-01)
羅貴祥
本文探討香港對本身社會的一些想像，可以被理解為與國家論述交涉甚至對抗的聲音。本文集中討論香港過去的海盜敘述與現在的農地敘述。稱這些為「敘述」，因為它們只能向外在環境投射一些想像，只是些模糊信念，不是統一連貫的意識形態系統。這些故事敘述的內容自相矛盾、犯駁，因為它們往往是集體經驗與想法的混合體，而不是深思熟慮的創作。在張保仔的傳奇裡，海盜組織是50年代香港難民社會的縮影。海盜故事敘述最吸引香港人的，是海盜從沒有政治意識形態的束縛。左右逢源以取得自主的求生狀態，被香港的敘述吸納，投射為在中西之間擔任買辦的殖民地故事。二十一世紀面對不斷壯大的中國主權國勢力，香港出現了另一種尚在起步的農地敘述。它不僅是關於農田耕作的，更與整體的香港土地使用有關。抗衡中國政府的霸權，香港農地故事敘述可以被視為一種本地充權、試圖重建社群的欲望。這種敘述鼓吹復興農業，並嵌入了不少當下世界的流行理念，例如生態運動、有機耕作、食物自主與安全、環保意識、文化保育等等。當代世界已經愈來愈受國家政府的控制、管治，逃離的空間似乎變得不可能，但這些敘述即使只是一種幻想，也可以讓本已被遺忘抹掉的東西若隱若現，造就看似不可能的改變。