Showing papers by "Chung Yuan Christian University published in 2012"
TL;DR: Polyimides rank among the most heat-resistant polymers and are widely used in high temperature plastics, adhesives, dielectrics, photoresists, nonlinear optical materials, membrane materials for separation, and Langmuir-Blodgett (LB) films, among others as mentioned in this paper.
1,534 citations
TL;DR: In this paper, the exceptional application of polyaniline/graphene composites (PAGCs) for corrosion protection of steel was reported. And the composites display outstanding barrier properties against O2 and H2O compared with polyaniniline and polyanile/clay composites.
605 citations
TL;DR: In this article, the authors focus on state-of-the-art polymeric hollow fiber membranes made from non-solvent-induced phase inversion and the potential of membrane processes for sustainable water and energy production.
352 citations
TL;DR: In this article, the authors investigated the relationship between green supply chain management (GSCM) drivers (organizational support, social capital and government involvement) and GSCM practices (green purchasing, cooperation with customers, eco-design and investment recovery).
323 citations
TL;DR: By comparing both results of polySBMA and poly(ethylene glycol) (PEG), it is found that the hydrated water molecules on the SB unit are more tightly bound than on the ethylene glycol (EG) unit before saturation, and the additional water molecules after forming the hydration layer inpolySBMA solutions show higher freedom than those in PEG.
Abstract: The strong surface hydration layer of nonfouling materials plays a key role in their resistance to nonspecific protein adsorption. Poly(sulfobetaine methacrylate) (polySBMA) is an effective material that can resist nonspecific protein adsorption and cell adhesion. About eight water molecules are tightly bound with one sulfobetaine (SB) unit, and additional water molecules over 8:1 ratio mainly swell the polySBMA matrix, which is obtained through the measurement of T(2) relaxation time by low-field nuclear magnetic resonance (LF-NMR). This result was also supported by the endothermic behavior of water/polySBMA mixtures measured by differential scanning calorimetry (DSC). Furthermore, by comparing both results of polySBMA and poly(ethylene glycol) (PEG), it is found that (1) the hydrated water molecules on the SB unit are more tightly bound than on the ethylene glycol (EG) unit before saturation, and (2) the additional water molecules after forming the hydration layer in polySBMA solutions show higher freedom than those in PEG. These results might illustrate the reason for higher resistance of zwitterionic materials to nonspecific protein adsorptions compared to that of PEGs.
294 citations
TL;DR: Novel single-phased white light-emitting KCaY(PO(4))(2):Eu(2+),Mn(2+) phosphors for light- Emitting diode (LED) applications were synthesized by conventional solid-state reaction.
Abstract: Novel single-phased white light-emitting KCaY(PO4)2:Eu2+,Mn2+ phosphors for light-emitting diode (LED) applications were synthesized by conventional solid-state reaction. The emission hue could be controlled by tuning the Eu2+/Mn2+ ratio via the energy transfer; the the emission hue of KCaY(PO4)2:Eu2+,Mn2+ varied from blue (0.1853, 0.2627) to white-light (0.3350, 0.3203) and eventually to purple (0.3919, 0.2867). The mechanism of energy transfer from a sensitizer Eu2+ to an activator Mn2+ in KCaY(PO4)2:Eu2+,Mn2+ phosphors was demonstrated to be an electric dipole–quadrupole interaction. Combining a NUV 405-nm chip and a white-emitting KCaY(PO4)2:1%Eu2+,4%Mn2+ phosphor produced a white-light NUV LED, demonstrating CIE chromaticity coordinates of (0.314, 0.329) and a color temperature of 6507 K.
254 citations
TL;DR: Different from traditional TSMC, this paper accomplishes finite convergence time for more general high-order MIMO systems and avoids the singular problem in the controller design.
239 citations
TL;DR: In this article, the densities, ρ, and refractive indices, nD, of deep eutectic solvents (DESs) were investigated at atmospheric pressure over the temperature range 298.15-333.
Abstract: Deep eutectic solvents (DES) are new emerging alternatives to conventional ionic liquids that may find a number of interesting applications in industrial and chemical processes. In this study, the densities, ρ, and refractive indices, nD, of the DESs (choline chloride + ethylene glycol) and (choline chloride + glycerol) and their aqueous mixtures were investigated at atmospheric pressure over the temperature range 298.15–333.15 K and across a complete composition range. The excess molar volumes, VE, and refractive index deviations, ΔnD, were also calculated from experimental results. The calculated excess molar volumes were negative at all temperatures over the entire range of composition considered, suggesting the presence of strong interactions between water and the DES in the mixtures. The refractive index deviations, on the other hand, were found positive in the entire concentration range. The calculated properties were fitted to a Redlich–Kister type equation to correlate them to the temperature and composition. The correlations used satisfactorily represent the densities and refractive indices of the pure DESs and their aqueous binary mixtures as functions of temperature and composition as indicated by the low overall average absolute deviations obtained in the calculations.
227 citations
TL;DR: There were significant differences in the TPACK of elementary teachers who used interactive whiteboards compared to teachers who did not use IWBs, and teachers' TPACK differed significantly on the basis of teachers' varying amounts of teaching experience.
Abstract: There has been an increasing tendency to enhance teachers' ability to apply educational technology. Few researchers have investigated with the relationships between the use of interactive whiteboards (IWBs) and the impact on the technological pedagogical and content knowledge (TPACK) of teachers. The purposes of the study were to examine Taiwanese elementary mathematics and science teachers' TPACK with respect to current use of IWBs. Associations between in-service teachers' TPACK and other factors were also examined. The IWB-based TPACK questionnaire was developed and validated in an elementary school context. The results indicated that there were significant differences in the TPACK of elementary teachers who used IWBs compared to teachers who did not use IWBs. Furthermore, elementary science teachers demonstrated significantly higher TPACK than elementary mathematics teachers. No significant difference was found in teachers' TPACK according to gender. The results also showed that teachers' TPACK differed significantly on the basis of teachers' varying amounts of teaching experience. Teachers who had more years of teaching experience demonstrated significantly higher TPACK than did teachers who had fewer years of teaching experience. The research implications of this study are provided along with suggestions.
200 citations
TL;DR: A robust EM clustering algorithm for Gaussian mixture models is developed, first creating a new way to solve these initialization problems, and then constructing a schema to automatically obtain an optimal number of clusters.
200 citations
TL;DR: In this article, a fuzzy-c-means (FCM) is employed to cluster the operation states for system load, wind-turbine generations (WTG), and photovoltaic (PV) in 8760h.
Abstract: Owing to the Kyoto Protocol and the growing depletion of natural resources, renewable energies have attracted much attention. This paper considers 25-kW wind-turbine generator, 5-kW PV and 30-kW diesel generator as unit sizes for generation planning in a stand-alone power system. The investment cost (installation and unit costs) and fuel cost are minimized while retaining the reliability requirement and CO emission limit. First, the fuzzy-c-means (FCM) is employed to cluster the operation states for system load, wind-turbine generations (WTG), and PV in 8760 h. Then, the Markov models for the system load, WTG, and photovoltaic (PV) are established. The Markov models are embedded into the genetic algorithm to determine the optimal sizes for WTG, PV, and the diesel generator. The simulation results reveal that computation time can be reduced greatly while optimality can be still retained, compared with the traditional method using chronological data.
TL;DR: In this article, the authors developed several hypotheses based on the agency theory self-interest perspective and tested the relationships among managerial ownership, corporate diversification, and firm performance using a sample of 98 emerging market firms listed on the Taiwan Stock Exchange.
TL;DR: In this paper, the authors assess renewable energy sources from a supply chain perspective and present an investigation of renewable energies focusing on four main components: renewable energy supply chain, renewable energy performance, and barriers and strategies to its development.
Abstract: Due to the depletion of traditional energy resources, such as crude oil, coal, and natural gas, many initiatives all over the world have addressed the efficient use or replacement of these resources. Several renewable energy sources have been introduced as alternatives to traditional sources to protect environmental resources and to improve the quality of life. This study assesses renewable energy sources from a supply chain perspective and presents an investigation of renewable energies focusing on four main components: renewable energy supply chain, renewable energy performance, and barriers and strategies to its development. The study provides managerial insights to governments, researchers, and stakeholders for the initiation of renewable energy use, and suggestions for overcoming the barriers to its development.
TL;DR: A new similarity measure formula for intuitionistic fuzzy sets induced by the Sugeno integral is proposed that uses a robust clustering method to recognize the patterns of intuitionism fuzzy sets.
TL;DR: In this article, a triblock copolymer was proposed to promote the nanophase separation between the hydrophobic polymer chain and hydrophilic ionic groups, and thus to form well-connected hydrophilic nanochannels that are responsible for the water uptake and proton conduction.
Abstract: Highly proton-conducting polymer electrolyte membrane (PEMs) materials are presented as alternatives to state-of-the-art perfluorinated polymers such as Nafion®. To achieve stable PEMs with efficient ionic nanochannels, novel fully aromatic ABA triblock copolymers (SP3O-b-PAES-b-SP3O) based on sulfonated poly(2,6-diphenyl-1,4-phenylene oxide)s (A, SP3O) and poly(arylene ether sulfone)s (B, PAES) were synthesized. This molecular design for a PEM was implemented to promote the nanophase separation between the hydrophobic polymer chain and hydrophilic ionic groups, and thus to form well-connected hydrophilic nanochannels that are responsible for the water uptake and proton conduction. Relative to other hydrocarbon-based PEMs, the triblock copolymer membranes showed a dramatic enhancement in proton conductivity under partially hydrated conditions, and superior thermal, oxidative and hydrolytic stabilities, suggesting that they have the potential to be utilized as alternative materials in applications operating under partly hydrated environments.
TL;DR: Poly(acrylic acid) was plasma-grafted on commercial poly(vinylidene fluoride) (PVDF) to introduce functional groups on the membrane surface that can support the nanoparticles, and it was found that plasma treatment at 100 W for 120 s followed by liquid grafting with 70% aqueous AA at 60°C for 2h maximized the number of TiO(2) binding sites.
TL;DR: In this article, a Tait-type equation was used to correlate high-pressure density data to temperature, T, pressure, P, and composition, x. The experimental data were used to derive other properties such as isothermal compressibility, isobaric expansivity and excess molar volume.
TL;DR: In this paper, a novel method for introducing zwitterionic polymers into nanofiltration membranes, with the aim of achieving high water flux and good anti-fouling performance, was proposed.
TL;DR: In this paper, the molar heat capacities of three choline chloride-based deep eutectic solvents (DESs), Reline, Ethaline and Glyceline, and their binary mixtures with water were determined using a heat flow differential scanning calorimeter.
TL;DR: In this article, a new set of vapor pressure data for the aqueous solutions of ethaline, glyceline, maline, and reline at different temperatures (30, 40, 50, 60, and 70 Ã 0.5 Ã ) and concentrations (20 Ã, 40, 60 Ã and 80 Ã Ã 1 ) were presented.
01 Apr 2012
TL;DR: The experimental results based on the Movielens dataset show that cluster ensembles can provide better recommendation performance than single clustering techniques in terms of recommendation accuracy and precision.
Abstract: Recommender systems, which recommend items of information that are likely to be of interest to the users, and filter out less favored data items, have been developed. Collaborative filtering is a widely used recommendation technique. It is based on the assumption that people who share the same preferences on some items tend to share the same preferences on other items. Clustering techniques are commonly used for collaborative filtering recommendation. While cluster ensembles have been shown to outperform many single clustering techniques in the literature, the performance of cluster ensembles for recommendation has not been fully examined. Thus, the aim of this paper is to assess the applicability of cluster ensembles to collaborative filtering recommendation. In particular, two well-known clustering techniques (self-organizing maps (SOM) and k-means), and three ensemble methods (the cluster-based similarity partitioning algorithm (CSPA), hypergraph partitioning algorithm (HGPA), and majority voting) are used. The experimental results based on the Movielens dataset show that cluster ensembles can provide better recommendation performance than single clustering techniques in terms of recommendation accuracy and precision. In addition, there are no statistically significant differences between either the three SOM ensembles or the three k-means ensembles. Either the SOM or k-means ensembles could be considered in the future as the baseline collaborative filtering technique.
TL;DR: In this article, the authors measured the densities of choline chloride:glycerol (GLY) and its aqueous mixtures in the temperature range (298.15-323.15) and pressure up to 50 MPa.
TL;DR: In this article, a polybenzimidazole (PBI) has been chemically bonded to silica nanoparticles (SNPs) through an ozone-mediated process using N-(p-carboxyphenyl)maleimide (pCPM) functionalized SNPs as precursors, to enhance the interfacial compatibility between SNPs and PBI in PBI/SNP nanocomposites.
TL;DR: In this article, the authors reviewed various concerns raised from the commercial biodiesel processing technology and addressed some innovative process intensification (PI) technologies, which likely bring appropriate technological improvement for biodiesel production.
Abstract: Biodiesel is commonly produced from lipid feedstock, animal fats and waste cooking oil by transesterification reaction. Considering the depletion of fossil fuel, biodiesel is gaining more attention as a renewable and environmental friendly fuel. The rapid growth of biodiesel industry thereafter has raised concerns to many existing commercial biodiesel enterprises. The major issues like feedstock flexibility, yield productivity and environmental impact are always the challenges to the continuous growth of conventional biodiesel processing technology. The processing of biodiesel is greatly hinged on the rich scientific background and technology development for better process advancement. The present paper reviews various concerns raised from the commercial biodiesel processing technology. It also addresses some innovative process intensification (PI) technologies, which likely bring appropriate technological improvement for biodiesel production.
TL;DR: The results indicate that banana peels dried at 120°C for 2h and ground into powder form led to a better performance in terms of both copper removal efficiency and energy consumption, which is beneficial to the application of these agro-waste materials for Cu removal from water and wastewater treatment.
TL;DR: In this article, the authors applied gold nanoparticles supported on silica for the selective hydrogenation of acetylene in excess ethylene that was close to current industrial practices, and the results of IR, TGA, XRD, and TEM showed that O2 plasma working under mild conditions (room temperature and low pressure) can efficiently remove the organic compounds without causing the aggregation of the gold particles.
TL;DR: In this paper, the crystal structure of Ca4Si2O7F2:Eu2+,Mn2+ was refined and determined from X-ray diffraction (XRD) profiles obtained using a synchrotron light source by the Rietveld refinement method.
Abstract: The crystal structure of Ca4Si2O7F2:Eu2+,Mn2+ was refined and determined from X-ray diffraction (XRD) profiles obtained using a synchrotron light source by the Rietveld refinement method. It was found to crystallize into a monoclinic structure with the P21/c(14) space group. On examining the Mn2+-concentration-dependent photoluminescence properties, we found that the emission colors could be tuned from blue (0.152, 0.112) to white-light (0.351, 0.332) and eventually to yellow (0.430, 0.423) through energy transfer by changing the Eu2+/Mn2+ ratio. Moreover, energy transfer from a sensitizer Eu2+ to an activator Mn2+ occurs via a resonance-type dipole–quadrupole interaction mechanism, and the critical distances of the energy transfer were calculated to be 11.66 A and 12.61 A using concentration quenching and spectral overlap methods, respectively. Combining a 400 nm near-ultraviolet (NUV) chip and a single-phase white-emitting (Ca0.96Eu0.01Mn0.03)4Si2O7F2 phosphor produced a white-light NUV LED with CIE chromaticity coordinates of (0.347, 0.338) and a warm color temperature of 4880 K.
TL;DR: This paper investigates the demand response achieved by the “smart energy management system” in a smart home environment, and aims to obtain the optimal temperature scheduling for air-conditioning according to the day-ahead electricity price and outdoor temperature forecasts.
Abstract: Smart home integrates disaster protection, medical care, entertainment and energy-saving systems, making the living environment more secure and comfortable. This paper investigates the demand response achieved by the “smart energy management system” in a smart home environment, and aims to obtain the optimal temperature scheduling for air-conditioning according to the day-ahead electricity price and outdoor temperature forecasts. Because the retail electricity price and temperature are predicted 24 h in advance and there exists uncertainty, the predicted retail electricity prices and temperatures are modeled by the fuzzy set. The immune clonal selection programming is employed to determine the day-ahead 24-h temperature schedule for air-conditioning. The electricity expense is hence minimized while comfort is still retained. The simulation result shows the applicability of the proposed method.
TL;DR: It is suggested that grooved topography has an in-depth potential for modulating the commitment of the stem cell lineages, which could benefit the development of advanced biomaterials for biomedical applications.
Abstract: Topographic cues have been recognized crucial on the modulation of cell behavior, and subsequent important for the design of implants, cell-based biomedical devices and tissue-engineered products. Grooved topography direct cells to align anisotropically on the substrates, resulting in an obvious morphological difference compared with the flat and the other topographies. This study aimed at investigating the effects of grooved topography on the differentiation of mesenchymal stem cells (MSCs) into osteoblasts, adipocytes and myoblasts. A series of submicron-grooved polystyrene substrates with equal groove-to-ridge ratio but different width and depth (width/depth (nm): 450/100, 450/350, 900/100, and 900/550) were fabricated based on electron beam lithography and soft lithography techniques. Primary rat MSCs (rMSCs) were cultured on these substrates without induction for differentiation for 6 days, and then subjected to induction for osteogenesis, adipogenesis and myogenesis. While the alignment of rMSCs strongly complied with the direction of the grooves and increased with groove depths, cell attachment on day 1 (~1.5 × 104/cm2) and cell proliferation after 6 days of culture (~5 × 104/cm2) were not significantly affected by substrate types. Osteogenesis, indicated by alkaline phosphatase activities and calcium deposit, was not significantly modulated by the grooved substrates, compared with the flat control, suggesting that cell alignment may not determine osteoinduction of rMSCs. On the other hand, adipogenesis, indicated by lipid production, was significantly enhanced by the grooved substrates compared with the flat surface (P < 0.001). On the other hand, myogenesis, indicated by desmin and MHC staining, was enhanced by the grooves in a time- and groove size-dependent manner compared with the flat control. The results suggested that grooved topography has an in-depth potential for modulating the commitment of the stem cell lineages, which could benefit the development of advanced biomaterials for biomedical applications.